Topical therapy for the treatment of skin malignancies using nanoparticles of taxanes

ABSTRACT

Disclosed are methods useful for the topical therapeutic treatment of skin malignancies including skin cancers and cutaneous metastases using compositions containing nanoparticles of paclitaxel or other taxanes.

CROSS-REFERENCE TO RELATED APPLICATION

This application is continuation of U.S. patent application Ser. No. 16/706,142, filed Dec. 6, 2019, which is a continuation of U.S. patent application Ser. No. 16/281,907, filed Feb. 21, 2019, now U.S. Pat. No. 10,555,898, which is a continuation of PCT/US2018/022540 filed Mar. 15, 2018, which claims the benefit of U.S. Provisional Application No. 62/471,561, filed Mar. 15, 2017. The contents of the referenced applications are incorporated into the present application by reference.

FIELD OF THE INVENTION

The present invention generally relates to the field of topical therapeutic treatment of skin malignancies including skin cancers and cutaneous metastases. In particular, the invention relates to the use of topical compositions comprising taxane nanoparticles for treatment of skin malignancies.

BACKGROUND OF THE INVENTION

Skin malignancies include skin cancers and cutaneous metastases. Skin cancers form in the tissues of the skin. There are several types of skin cancers which include melanoma (malignant melanoma), basal cell carcinoma, squamous cell carcinoma, neuroendocrine carcinoma of the skin, Merkel cell tumors, dermatofibrosarcoma protruberans, and Kaposi's sarcoma. The major types of skin cancers include melanoma, basal cell carcinoma, and squamous cell carcinoma. Melanoma is a skin cancer that forms in melanocytes (skin cells that make pigments). Basal cell carcinoma forms in the lower part of the epidermis and squamous cell carcinoma forms in squamous cells. Neuroendocrine carcinoma of the skin forms in neuroendocrine cells. The vast majority of skin cancers are basal cell carcinomas and squamous cell carcinomas, and they generally do not spread to other parts of the body (metastasize). Melanomas tend to spread to other parts of the body. Kaposi's sarcoma is a relatively rare type of skin malignancy that afflicts the elderly or those with an abnormal immune system such as those with AIDS. Kaposi's sarcoma is a lesion (tumor) of the skin characterized by soft purplish plaques and papules that form nodules on the skin.

A cutaneous (skin) metastasis refers to a growth of cancer cells in the skin originating from an internal cancer or a skin cancer such as melanoma. A cutaneous metastasis occurs when cancerous cells break away from the primary cancer tumor and travel to the skin typically through the blood circulation or lymphatic system. Cutaneous metastases have been reported as manifestations of the following cancers: breast, lung, nasal sinus, larynx, oral cavity, colorectal, stomach, ovary, testis, bladder, prostate, cervical, vaginal, thyroid, endometrial, kidney, esophagus, pancreas, liver, melanoma and Kaposi's sarcoma (including AIDS-related Kaposi's sarcoma). Cutaneous metastases are increasingly prevalent and occur in approximately 10% of patients with metastatic cancer (Lookingbill et. al., Cutaneous metastases in patients with metastatic carcinoma: A retrospective study of 4020 patients, J Am Acad Dermatol 29:228-236, 1993). Women with skin metastases have the following distribution in decreasing order of frequency of primary malignancies: breast, ovary, oral cavity, lung, and large intestine. In men, the distribution is as follows: lung, large intestine, oral cavity, kidney, breast, esophagus, pancreas, stomach, and liver. (Alcaraz et al., Cutaneous Metastases from Internal Malignancies: A Clinicopathologic and Immunohistochemical Review, Am J Dermatopathol 34:347-393, 2012). With advances in cancer treatment, patients are living longer and thus, are more likely to develop cutaneous metastases.

Generally, a cutaneous metastasis lesion is a firm, round or oval mobile, non-painful nodule or nodules with intact overlying epidermis. Sometimes nodules develop ulceration and secondary infection. Other signs of a skin metastasis can be the presence of plaques, papules, or red patches. Cutaneous metastases can cause pain, infection, bleeding and/or disfigurement, and can negatively impact the quality of life of the patient.

The incidence of cutaneous metastases in patients with breast carcinoma was recently reported as 23.9% (Lookingbill et. al.). Cutaneous metastases from breast carcinoma are the most common metastases observed by dermatologists (De Giorgi et. al., Cutaneous manifestations of breast carcinoma, Dermatol Therapy, 23:581-589, 2010). These cutaneous metastases most commonly occur on the chest wall and abdomen, but may also occur at the extremities and on the head and neck region. Nodules are the most common form of these cutaneous metastases. They range in size from 1 to 3 cm and are firm solitary or multiple lesions in the dermis or subcutaneous tissue.

Various treatments for skin cancer and cutaneous metastases are available including systemic therapy and skin-directed therapy. However, systemic therapy has limited efficacy with respect to treatment of cutaneous metastases (Spratt et al., Efficacy of Skin-Directed Therapy for Cutaneous Metastases from Advanced Cancer: A Meta-Analysis, J Clin Oncol, 32:3144-3155, 2014).

Skin-directed therapy includes electrochemotherapy (ECT), photodynamic therapy (PDT), radiotherapy (RT), intralesional therapy (ILT), and topical therapy. ECT, PDT, RT, and ILT all require administration by a medical practitioner or technician, whereas topical therapy can be administered by the patient. Thus, topical therapy can be less costly than other therapies and can also allow for greater patient compliance since the therapy can be administered by the patient at home. However, topical therapy that included compositions of imiquimod or miltefosine for the treatment of cutaneous metastases had low response rates and only showed improved response rates when combined with other skin-directed therapies (Spratt et. al.). In a meta-analysis of 47 prospective studies of 4,313 cutaneous metastases, the objective response rate to the aforementioned therapies (including radiotherapy) was 60.2% (Spratt et al.). ECT demonstrated the best response rate (complete response rate 47.5%); however, ECT is an inpatient procedure requiring general anesthesia and often results in notable pain and dermatologic toxicity (inflammation, hyperpigmentation, and ulceration) (Cabula et al., Electrochemotherapy in the Treatment of Cutaneous Metastases from Breast Cancer: A Multicenter Cohort Analysis, Ann Surg Oncol (2015) 22:S442-S450). The less invasive alternatives, such as intralesional therapy and topical therapy demonstrate reduced efficacy in comparison to ECT. When effective reduction of cutaneous metastases cannot be achieved, as is often the case, healthcare providers must fall back on palliative wound care remedies (Fernandez-Anton Martinez, et al., Metástasis cutáneas de origen visceral, Actas Dermosifiliogr. 2013; 104(10):841-853). Thus, the availability of topical therapeutic compositions that are efficacious in treating cutaneous metastases without the need to combine the therapy with other skin-directed therapies would be beneficial. There is therefore a significant unmet need for an effective, less invasive alternative therapy for cutaneous metastases in patients already struggling with significant morbidity from the symptoms of and treatments for advanced primary cancer.

Delivery of therapeutic drugs into viable epidermis and dermis of the skin can be a challenge due to the barrier properties of the stratum corneum, the outermost layer of the epidermis. The delivery of poorly water soluble drugs into the skin can be even more of a challenge. Skin penetration enhancers have been employed in topical drug formulations to increase the penetration of drugs into the skin and have had some success. However, some penetration enhancers such as solvents and surfactants can be irritating to the skin. Volatile silicone fluids have been employed in topical formulations to increase the penetration of drugs into the skin; however, high concentrations of volatile silicone fluids, i.e., 25% and greater, and/or combinations of volatile silicone fluids with other potential skin irritating compounds such as alcohols, e.g., C₁ to C₄ aliphatic alcohols, surfactants, other penetration enhancers, and other volatile solvents have been needed to produce the penetration enhancement effect. Additionally, some penetration enhancers will cause the drug to penetrate transdermally and be systemically absorbed, which is not desirable when only treating a condition of the skin (e.g., epidermis and/or dermis). Other topical delivery systems have been employed where the drug is chemically modified with surfactants and other substances, but these materials can also be irritating to the skin.

Taxanes, including paclitaxel and docetaxel, have been used for the treatment of cancer for many years. These compounds are typically characterized as being poorly water soluble. The cancer treatment formulation initially developed for intravenous (IV) infusion injection, TAXOL® (BMS), is paclitaxel dissolved in a 50:50 v/v mixture of polyethoxylated castor oil (CREMOPHOR® EL) and dehydrated ethanol. However, the systemic use of this formulation results in significant clinical toxicity (Rowinsky et al. 1993). Substantial effort has been devoted to the development of CREMOPHOR EL-free formulations of paclitaxel (Ma and Mumper, 2013). One such formulation is disclosed in U.S. Pat. No. 8,221,779, herein incorporated by reference, which discloses injectable aqueous compositions of antimitotic drug microparticles, including paclitaxel, useful for the treatment of cancers by intraperitoneal and intravenous (IV) injection of the compositions.

Topical treatment of skin cancers currently includes topical formulations of 5-fluorouracil (5-FU), imiquimod, and ingenol mebutate. However, the use of these formulations can cause local skin irritation such as burning, redness, dryness, pain, swelling, itching, tenderness, and ulceration at the site of application.

Currently, there are no FDA approved topical taxane formulations for the treatment of skin cancer or cutaneous metastases in the U.S. Previous topical therapy treatments of cutaneous metastases using compositions containing other active ingredients may have been ineffective in part, because of the inability of the composition to penetrate into the skin to the affected tissue.

SUMMARY OF THE INVENTION

The present invention provides solutions to the aforementioned limitations and deficiencies in the art relating to the treatment of skin malignancies including skin cancers and cutaneous metastases. Disclosed is a topical therapy that utilizes a topical composition with enhanced dermal penetration for the delivery of taxane nanoparticles to skin malignancies including skin cancers and cutaneous metastases providing effective treatment with low to negligible local skin irritation. In certain instances, the treatment methods of the present invention can be used without the need to combine them with other known skin-directed therapies such as those discussed above.

In one aspect of the invention, disclosed is a method of treating a skin malignancy in a subject in need of treatment, the method comprising topically administering (topically applying) to an affected area of the subject a composition comprising a plurality of taxane nanoparticles. The “affected area” of a skin malignancy can include at least a portion of the skin where the skin malignancy lesion is visibly present on the outermost surface of the skin or directly underneath the surface of the skin (epithelial/dermal covering), and can include areas of the skin in the proximity of the skin malignancy likely to contain visibly undetectable preclinical lesions. In some embodiments, the taxane nanoparticles are suspended within the composition. In other embodiments, the taxane nanoparticles have a mean particle size (number) from 0.1 microns to 1.5 microns. In various embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles, or any combination of such nanoparticles. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles. In some embodiments, the paclitaxel nanoparticles have a specific surface area (SSA) of at least 18 m²/g, or from 18 m²/g to 40 m²/g. The concentration of the taxane nanoparticles in the compositions is at a concentration effective to provide a therapeutic improvement in the skin malignancy, which can be a skin cancer or a cutaneous metastasis. In some embodiments, the effective concentration of the taxane nanoparticles or paclitaxel nanoparticles is about 0.15 to about 2% w/w, or 0.1 to 5% w/w. In some embodiments, the composition is anhydrous. In some embodiments, the composition is a hydrophobic composition and can comprise a hydrophobic carrier. In still other embodiments, the hydrophobic carrier is non-volatile and/or is non-polar. In various embodiments, the hydrophobic carrier comprises a hydrocarbon which can be petrolatum, mineral oil, or paraffin wax, or mixtures thereof. In some embodiments, the mineral oil is heavy mineral oil. In some embodiments, the hydrophobic carrier is greater than 50% w/w of the composition. The hydrophobic composition can further comprise one or more volatile silicone fluids. In some embodiments, the volatile silicone fluid is at a concentration of 5 to 24% w/w of the composition and can be cyclomethicone. In some embodiments, the cyclomethicone is cyclopentasiloxane. In various embodiments, the composition is a semi-solid composition and can be an ointment. In various embodiments, the composition does not contain volatile C₁-C₄ aliphatic alcohols or C₁-C₅ aliphatic alcohols, and/or does not contain additional penetration enhancers, and/or does not contain additional volatile solvents, and/or does not contain surfactants, and/or does not contain a protein or albumin. In some embodiments, the skin malignancy is a skin cancer. In some embodiments, the skin cancer is melanoma, basal cell carcinoma, squamous cell carcinoma, and/or Kaposi's sarcoma. In some embodiments, the skin malignancy is a cutaneous metastasis. In some embodiments, the cutaneous metastasis is from lung cancer, breast cancer, colon cancer, oral cancer, ovarian cancer, kidney cancer, esophageal cancer, stomach cancer, and/or liver cancer; and/or Kaposi's sarcoma (including AIDS-related Kaposi's sarcoma). In still other embodiments, the therapeutic method does not include additional skin-directed therapies.

In another aspect of the invention, there is disclosed a method of enhancing penetration of taxane nanoparticles into a skin malignancy of a subject, the method comprising topically applying to the affected area a hydrophobic composition comprising a continuous hydrophobic carrier, one or more volatile silicone fluids, and a plurality of taxane nanoparticles. In some embodiments, the taxane nanoparticles are suspended within the composition. In other embodiments, the taxane nanoparticles have a mean particle size (number) from 0.1 microns to 1.5 microns. In various embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles, or any combination of such nanoparticles. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles. In some embodiments, the paclitaxel nanoparticles have a specific surface area (SSA) of at least 18 m²/g, or from 18 m²/g to 40 m²/g. In some embodiments, the concentration of the taxane nanoparticles or paclitaxel nanoparticles is about 0.15 to about 2% w/w, or 0.1 to 5% w/w. In some embodiments, the composition is anhydrous. In some embodiments, the composition is a hydrophobic composition and can comprise a hydrophobic carrier. In still other embodiments, the hydrophobic carrier is non-volatile and/or is non-polar. In various embodiments, the hydrophobic carrier comprises a hydrocarbon which can be petrolatum, mineral oil, or paraffin wax, or mixtures thereof. In some embodiments, the mineral oil is heavy mineral oil. In some embodiments, the hydrophobic carrier is greater than 50% w/w of the composition. The hydrophobic composition can further comprise one or more volatile silicone fluids. In some embodiments, the volatile silicone fluid is at a concentration of 5 to 24% w/w of the composition and can be cyclomethicone. In some embodiments, the cyclomethicone is cyclopentasiloxane. In various embodiments, the composition is a semi-solid composition and can be an ointment and can have a viscosity of 25,000 cps to 500,000 cps as measured with a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds. In various embodiments, the composition does not contain volatile C₁-C₄ aliphatic alcohols or C₁-C₅ aliphatic alcohols, and/or does not contain additional penetration enhancers, and/or does not contain additional volatile solvents, and/or does not contain surfactants, and/or does not contain a protein or albumin. In some embodiments, the skin malignancy is a skin cancer. In some embodiments, the skin cancer is melanoma, basal cell carcinoma, squamous cell carcinoma, and/or Kaposi's sarcoma. In some embodiments, the skin malignancy is a cutaneous metastasis. In some embodiments, the cutaneous metastasis is from lung cancer, breast cancer, colon cancer, oral cancer, ovarian cancer, kidney cancer, esophageal cancer, stomach cancer, and/or liver cancer; and/or Kaposi's sarcoma (including AIDS-related Kaposi's sarcoma). In some embodiments, the penetration of the taxane nanoparticles from the hydrophobic composition into the skin malignancy is greater than the penetration of taxane nanoparticles into the skin malignancy from topically applying a hydrophobic composition that comprises a plurality of taxane nanoparticles and that does not contain one or more volatile silicone fluids.

In another aspect of the inventions, disclosed is a method of enhancing penetration of taxane nanoparticles into a skin malignancy of a subject, the method comprising topically applying a hydrophobic composition comprising a plurality of taxane nanoparticles to the affected area, wherein the penetration of the taxane nanoparticles from the hydrophobic composition into the skin malignancy is greater than the penetration of taxane nanoparticles into the skin malignancy from topically applying an aqueous based composition comprising a plurality of taxane nanoparticles. In some embodiments, the taxane nanoparticles have a mean particle size (number) from 0.1 microns to 1.5 microns. In some embodiments, taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles, or any combination of such nanoparticles. In some embodiments, hydrophobic composition further comprises a hydrophobic carrier.

As disclosed in international publication WO 2017/049083 (application PCT/US2016/052133) herein incorporated by reference, it was found that hydrophobic compositions of the present invention having a volatile silicone fluid at concentrations less than 25% w/w in combination with an anhydrous hydrophobic carrier exhibited greater skin penetration (i.e., penetration into the epidermal and dermal portions of the skin) of taxane nanoparticles as compared to the skin penetration of taxane nanoparticles from the hydrophobic carrier alone. Surprisingly, it was also discovered that, other than the low amounts of volatile silicone fluid (less than 25 w/w %), the addition of other skin penetration enhancers to the hydrophobic compositions had little or no effect on the skin penetration of the compositions. Therefore, the compositions of the present invention can be free of (do not have to include) these additional skin penetration enhancers (e.g., surfactants, volatile solvents, alcohols, C₁-C₄ aliphatic alcohols or C₁-C₅ aliphatic alcohols), which can be helpful in reducing skin irritation when the compositions of the present invention are applied to the skin. Even more surprising is that the enhanced penetration was accomplished with low concentrations of cyclomethicone, i.e., less than 25% w/w. Additionally, the taxane nanoparticles are not transdermally delivered with these compositions initially after administration, which is a favorable feature because transdermal delivery (systemic absorption) is not desired when treating the skin (epidermis and dermis). Furthermore, the skin penetration (i.e., penetration into the dermal or epidermal portions of the skin) of taxane nanoparticles from the compositions of the present invention was far superior to the skin penetration of taxane nanoparticles from aqueous based compositions, even though the aqueous based compositions contained a skin penetration enhancer. Additionally, it was found that the taxane nanoparticles were stable and did not exhibit crystal grow over time in the hydrophobic compositions of the present invention.

Hydrophobic compositions which comprise nanoparticles of a taxane, e.g., paclitaxel, and a volatile silicone fluid in combination with a hydrophobic carrier, are especially suitable for the topical treatment of skin malignancies including skin cancers and cutaneous metastases because of the aforementioned enhanced penetration properties of these compositions into the epidermis and dermis portions of the skin. The hydrophobic carrier can be the continuous phase of the composition with the nanoparticles suspended therein.

Also, disclosed in the context of the present invention are the following embodiments 1 to 71:

-   Embodiment 1 is a method of treating a skin malignancy in a subject     in need of treatment, the method comprising topically administering     to an affected area of the subject a composition comprising a     plurality of taxane nanoparticles. -   Embodiment 2 is the method of embodiment 1, wherein the taxane     nanoparticles are suspended within the composition. -   Embodiment 3 is the method of any one of embodiments 1 to 2, wherein     the taxane nanoparticles have a mean particle size (number) from 0.1     microns to 1.5 microns. -   Embodiment 4 is the method of any one of embodiments 1 to 3, wherein     the taxane nanoparticles are paclitaxel nanoparticles, docetaxel     nanoparticles, or cabazitaxel nanoparticles. -   Embodiment 5 is the method of embodiment 4, wherein the taxane     nanoparticles are paclitaxel nanoparticles. -   Embodiment 6 is the method of embodiment 5, wherein the paclitaxel     nanoparticles have a specific surface area (SSA) of at least 18     m²/g. -   Embodiment 7 is the method of embodiment 6, wherein the paclitaxel     nanoparticles have a specific surface area (SSA) of 18 m²/g to 40     m²/g. -   Embodiment 8 is the method of any of embodiments 1 to 7, wherein the     concentration of the taxane nanoparticles is at a concentration     effective to provide a therapeutic improvement in the skin     malignancy. -   Embodiment 9 is the method of embodiment 8, wherein the     concentration of the paclitaxel nanoparticles is about 0.15 to about     2% w/w, or 0.1 to 5% w/w. -   Embodiment 10 is the method of any one of embodiments 1 to 9,     wherein the composition is anhydrous. -   Embodiment 11 is the method of any one of embodiments 1 to 10,     wherein the composition is a hydrophobic composition. -   Embodiment 12 is the method of embodiment 11, wherein the     hydrophobic composition comprises a hydrophobic carrier. -   Embodiment 13 is the method of embodiment 12, wherein the     hydrophobic carrier is non-volatile. -   Embodiment 14 is the method of any one of embodiments 12 to 13,     wherein the hydrophobic carrier is non-polar. -   Embodiment 15 is the method of any one of embodiments 12 to 14,     wherein the hydrophobic carrier comprises a hydrocarbon. -   Embodiment 16 is the method of embodiment 15, wherein the     hydrocarbon is petrolatum, mineral oil, or paraffin wax, or mixtures     thereof. -   Embodiment 17 is the method of embodiment 16, wherein the mineral     oil is heavy mineral oil. -   Embodiment 18 is the method of any one of embodiments 12 to 17,     wherein the hydrophobic carrier is greater than 50% w/w of the     composition. -   Embodiment 19 is the method of any one of embodiments 12 to 18,     wherein the hydrophobic composition comprises one or more volatile     silicone fluids. -   Embodiment 20 is the method of embodiment 19, wherein the     concentration of the one or more volatile silicone fluids is from 5     to 24% w/w of the composition. -   Embodiment 21 is the method of embodiment 20, wherein the volatile     silicone fluid is cyclomethicone. -   Embodiment 22 is the method of embodiment 21, wherein the     cyclomethicone is cyclopentasiloxane. -   Embodiment 23 is the method of any one of embodiments 1 to 22,     wherein the composition is a semi-solid composition. -   Embodiment 24 is the method of embodiment 23, wherein the semi-solid     composition is an ointment. -   Embodiment 25 is the method of any one of embodiments 1 to 24,     wherein the composition does not contain volatile C₁-C₄ aliphatic     alcohols. -   Embodiment 26 is the method of any one of embodiments 1 to 25,     wherein the composition does not contain additional penetration     enhancers. -   Embodiment 27 is the method of any one of embodiments 1 to 26,     wherein the composition does not contain additional volatile     solvents. -   Embodiment 28 is the method of any one of embodiments 1 to 27,     wherein the composition does not contain surfactants. -   Embodiment 29 is the method of any one of embodiments 1 to 28,     wherein the composition does not contain a protein or albumin. -   Embodiment 30 is the method of any one of embodiments 1 to 29,     wherein the skin malignancy is a skin cancer. -   Embodiment 31 is the method of embodiment 30, wherein the skin     cancer is melanoma, basal cell carcinoma, squamous cell carcinoma,     or Kaposi's sarcoma. -   Embodiment 32 is the method of any one of embodiments 1 to 29,     wherein the skin malignancy is a cutaneous metastasis. -   Embodiment 33 is the method of embodiment 32, wherein the cutaneous     metastasis is from lung cancer, breast cancer, colon cancer, oral     cancer, ovarian cancer, kidney cancer, esophageal cancer, stomach     cancer, liver cancer, and/or Kaposi's sarcoma. -   Embodiment 34 is the method of any one of embodiments 1 to 33,     wherein the method does not include additional skin-directed     therapies. -   Embodiment 35 is a method of enhancing penetration of taxane     nanoparticles into a skin malignancy of a subject, the method     comprising topically applying to the affected area a hydrophobic     composition comprising a continuous hydrophobic carrier, one or more     volatile silicone fluids, and a plurality of taxane nanoparticles. -   Embodiment 36 is the method of embodiment 35, wherein the taxane     nanoparticles are suspended within the hydrophobic composition. -   Embodiment 37 is the method of any one of embodiments 35 to 36,     wherein the taxane nanoparticles have a mean particle size (number)     from 0.1 microns to 1.5 microns. -   Embodiment 38 is the method of any one of embodiments 35 to 37,     wherein the taxane nanoparticles are paclitaxel nanoparticles,     docetaxel nanoparticles, or cabazitaxel nanoparticles. -   Embodiment 39 is the method of embodiment 38, wherein the taxane     nanoparticles are paclitaxel nanoparticles. -   Embodiment 40 is the method of embodiment 39, wherein the paclitaxel     nanoparticles have a specific surface area (SSA) of at least 18     m²/g. -   Embodiment 41 is the method of embodiment 40, wherein the paclitaxel     nanoparticles have a specific surface area (SSA) of 18 m²/g to 40     m²/g. -   Embodiment 42 is the method of any one of embodiments 39 to 42     wherein the concentration of the paclitaxel nanoparticles is about     0.15 to about 2% w/w, or 0.1 to 5% w/w. -   Embodiment 43 is the method of any one of embodiments 35 to 42,     wherein the composition is anhydrous. -   Embodiment 44 is the method of any one of embodiments 35 to 43,     wherein the hydrophobic carrier is non-volatile. -   Embodiment 45 is the method of any one of embodiments 35 to 44,     wherein the hydrophobic carrier is non-polar. -   Embodiment 46 is the method of any one of embodiments 35 to 45,     wherein the hydrophobic carrier comprises a hydrocarbon. -   Embodiment 47 is the method of embodiment 46, wherein the     hydrocarbon is petrolatum, mineral oil, or paraffin wax, or mixtures     thereof. -   Embodiment 48 is the method of embodiment 47, wherein the mineral     oil is heavy mineral oil. -   Embodiment 49 is the method of any one of embodiments 35 to 48,     wherein the hydrophobic carrier is greater than 50% w/w of the     composition. -   Embodiment 50 is the method of any one of embodiments 35 to 49,     wherein the concentration of the one or more volatile silicone     fluids is from 5 to 24% w/w of the composition. -   Embodiment 51 is the method of embodiment 50, wherein the volatile     silicone fluid is cyclomethicone. -   Embodiment 52 is the method of embodiment 51, wherein the     cyclomethicone is cyclopentasiloxane. -   Embodiment 53 is the method of any one of embodiments 35 to 52,     wherein the composition is a semi-solid composition. -   Embodiment 54 is the method of embodiment 53, wherein the semi-solid     composition is an ointment. -   Embodiment 55 is the method of any one of embodiments 53 to 54,     wherein the viscosity of the composition is 25,000 cps to 500,000     cps as measured with a Brookfield RV viscometer on a helipath stand     with the helipath on, with a T-E spindle at 10 RPM at room     temperature for 45 seconds. -   Embodiment 56 is the method of any one of embodiments 35 to 55,     wherein the composition does not contain volatile C₁-C₄ aliphatic     alcohols. -   Embodiment 57 is the method of any one of embodiments 35 to 56,     wherein the composition does not contain additional penetration     enhancers. -   Embodiment 58 is the method of any one of embodiments 35 to 57,     wherein the composition does not contain additional volatile     solvents. -   Embodiment 59 is the method of any one of embodiments 35 to 58,     wherein the composition does not contain surfactants. -   Embodiment 60 is the method of any one of embodiments 35 to 59,     wherein the composition does not contain a protein or albumin. -   Embodiment 61 is the method of any one of embodiments 35 to 60,     wherein the skin malignancy is a skin cancer. -   Embodiment 62 is the method of embodiment 61, wherein the skin     cancer is selected from melanoma, basal cell carcinoma, and squamous     cell carcinoma. -   Embodiment 63 is the method of any one of embodiments 35 to 60,     wherein the skin malignancy is a cutaneous metastasis. -   Embodiment 64 is the method of embodiment 63, wherein the cutaneous     metastasis is from lung cancer, breast cancer, colon cancer, oral     cancer, ovarian cancer, kidney cancer, esophageal cancer, stomach     cancer, liver cancer, and/or Kaposi's sarcoma. -   Embodiment 65 is the method of any one of embodiments 35 to 64,     wherein the penetration of the taxane nanoparticles from the     hydrophobic composition into the skin malignancy is greater than the     penetration of taxane nanoparticles into the skin malignancy from     topically applying a hydrophobic composition that comprises a     plurality of taxane nanoparticles and that does not contain one or     more volatile silicone fluids. -   Embodiment 66 is a method of enhancing penetration of taxane     nanoparticles into a skin malignancy of a subject, the method     comprising topically applying a hydrophobic composition comprising a     plurality of taxane nanoparticles to the affected area, wherein the     penetration of the taxane nanoparticles from the hydrophobic     composition into the skin malignancy is greater than the penetration     of taxane nanoparticles into the skin malignancy from topically     applying an aqueous based composition comprising a plurality of     taxane nanoparticles. -   Embodiment 67 is the method of embodiment 66, wherein the taxane     nanoparticles have a mean particle size (number) from 0.1 microns to     1.5 microns. -   Embodiment 68 is the method of any one of embodiments 66 to 67,     wherein the taxane nanoparticles are paclitaxel nanoparticles,     docetaxel nanoparticles, or cabazitaxel nanoparticles. -   Embodiment 69 is the method of any one of embodiments 66 to 68,     wherein the hydrophobic composition further comprises a hydrophobic     carrier. -   Embodiment 70 is the method of any one of embodiments 66 to 69,     wherein the skin malignancy is a skin cancer or a cutaneous     metastasis. -   Embodiment 71 is the method of any one of embodiments 66 to 70,     wherein the hydrophobic composition comprises a continuous     hydrophobic phase having the plurality of taxane nanoparticles     suspended therein.

The terms “nanoparticle”, “nanoparticles”, and “nanoparticulate”, as used herein with regard to taxane particles, represent the mean particle size (based on the number-weighted differential distribution, designated as “number”) of the taxane particles which is from 0.01 microns to 1.5 microns (10 nm to 1500 nm) or preferably from 0.1 microns to 1.5 microns (100 nm to 1500 nm).

The term “water soluble,” as used herein, describes compounds that have a solubility in water of greater than 10 mg/mL or greater at room temperature.

The term “poorly water soluble,” as used herein, describes compounds that have a solubility in water of less than or equal to 10 mg/mL at room temperature.

The term “hydrophobic,” as used herein, describes compounds, compositions, or carriers that have a solubility in water of less than or equal to 10 mg/mL at room temperature.

The term “volatile,” as used herein, describes compounds, compositions, or carriers that have a vapor pressure greater than or equal to 10 Pa at room temperature.

The term “non-volatile,” as used herein, describes compounds, compositions, or carriers that have a vapor pressure less than 10 Pa at room temperature.

The term “anhydrous,” as used herein with regard to the compositions or carriers of the invention, means that less than 3% w/w, preferably less than 2% w/w, more preferably less than 1% w/w, or most preferably 0% w/w of water is present in the compositions or carriers. This can account for small amounts of water being present (e.g., water inherently contained in any of the ingredients of the compositions or carriers, water contracted from the atmosphere, etc.).

The terms “skin” or “cutaneous” as used herein mean the epidermis and/or the dermis.

The term “skin malignancy” as used herein includes skin cancers and cutaneous metastases.

The “affected area” of a skin malignancy can include at least a portion of the skin where the skin malignancy lesion (tumor) is visibly present on the outermost surface of the skin or directly underneath the surface of the skin (epithelial/dermal covering), and can include areas of the skin in the proximity of the skin malignancy likely to contain visibly undetectable preclinical lesions.

The terms “cutaneous metastasis”, “cutaneous metastases” (plural), “skin metastasis”, “skin metastases” (plural), “cutaneous metastatic lesion(s)”, “skin metastatic lesion(s)”, “cutaneous metastasis lesion(s)”, “skin metastasis lesion(s)”, “skin metastatic disease”, or “cutaneous metastatic disease” as used herein means the manifestation of a malignancy in the skin as a secondary growth (tumor/lesion) arising from the primary growth of a cancer tumor at another location of the body. Spread from the primary tumor can be through the lymphatic or blood circulation systems, or by other means.

The terms “skin-directed therapy” or “skin-directed therapies” as used herein means electrochemotherapy (ECT), photodynamic therapy (PDT), radiotherapy (RT), intralesional therapy (ILT), or topical therapy.

The terms “subject” or “patient” as used herein mean a vertebrate animal. In some embodiments, the vertebrate animal can be a mammal. In some embodiments, the mammal can be a primate, including a human.

The term “room temperature” (RT) as used herein, means 20-25° C.

The term “penetration enhancer” or “skin penetration enhancer” as used herein, means a compound or a material or a substance that facilitates drug absorption into the skin (epidermis and dermis).

The term “surfactant” or “surface active agent” as used herein, means a compound or a material or a substance that exhibits the ability to lower the surface tension of water or to reduce the interfacial tension between two immiscible substances.

Unless otherwise specified, the percent values expressed herein are weight by weight and are in relation to the weight of the total composition.

The term “about” or “approximately” are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment the terms are defined to be within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

For this application, a number value with one or more decimal places can be rounded to the nearest whole number using standard rounding guidelines, i.e. round up if the number being rounded is 5, 6, 7, 8, or 9; and round down if the number being rounded is 0, 1, 2, 3, or 4. For example, 3.7 can be rounded to 4.

The words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”) or “containing” (and any form of containing, such as “contains” and “contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

The use of the word “a” or “an” when used in conjunction with the terms “comprising,” “having,” “including,” or “containing” (or any variations of these words) may mean “one,” but it is also consistent with the meaning of “one or more,” “at least one,” and “one or more than one.”

The compositions and methods for their use can “comprise,” “consist essentially of,” or “consist of” any of the ingredients or steps disclosed throughout the specification. With respect to the phrase “consisting essentially of,” a basic and novel property of the compositions of the present invention are their ability to topically treat skin malignancies. With respect to hydrophobic compositions of the present invention, a basic and novel property includes the ability to a skin malignancy and the ability to have the nanoparticles more effectively penetrate into the epidermal and dermal layers of the skin with limited to no penetration transdermally. This can be achieved without the use of C₁-C₄ aliphatic alcohols or C₁-C₅ aliphatic alcohols, surfactants, and additional skin penetration enhancers and additional volatile solvents other than a volatile silicone fluid(s) (e.g., cyclomethicone or cyclopentasiloxane, or a combination thereof).

“Limited,” “reduced,” or “minimal” when modifying the phrase “penetration transdermally” means wherein less than 0.01 μg/cm² of the drug nanoparticles penetrate through human cadaver skin when the composition is applied to the human cadaver skin as determined by an in vitro Franz diffusion cell system.

It is contemplated that any embodiment discussed in this specification can be implemented with respect to any method or composition of the invention, and vice versa. Furthermore, compositions of the invention can be used to achieve methods of the invention.

Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating specific embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 graphically shows the concentration of paclitaxel (μg/cm2) delivered in vitro into the epidermis for formulas F1 through F7.

FIG. 2 graphically shows the concentration of paclitaxel (μg/cm2) delivered in vitro into the epidermis for formulas F6*(repeat analysis) and F8 through F13.

FIG. 3 graphically shows the concentration of paclitaxel (μg/cm2) delivered in vitro into the dermis for formulas F1 through F7.

FIG. 4 graphically shows the concentration of paclitaxel (μg/cm2) delivered in vitro into the dermis for formulas F6*(repeat analysis) and F8 through F13.

FIG. 5 is a photo of a skin metastatic lesion on the chest of a woman with Stage 4 breast cancer at baseline (Day 1).

FIG. 6 is a photo of a skin metastatic lesion on the chest of a woman with Stage 4 breast cancer at Day 8 after topical treatment.

FIG. 7 is a photo of a skin metastatic lesion on the chest of a woman with Stage 4 breast cancer at Day 15 after topical treatment.

FIG. 8 is a photo of a skin metastatic lesion on the chest of a woman with Stage 4 breast cancer at Day 29 after topical treatment.

DETAILED DESCRIPTION OF THE INVENTION

In some aspects, the invention relates to methods of treatment of skin malignancies including skin cancers and cutaneous metastases in a patient by topically applying to the affected area (topical therapy) a composition comprising a taxane(s). In some embodiments, the taxane is paclitaxel. In other embodiments, the taxane is docetaxel or cabazitaxel. In further embodiments, a combination of taxanes can be used (e.g., paclitaxel and docetaxel, or paclitaxel and cabazitaxel, or docetaxel and cabazitaxel, or paclitaxel, docetaxel, and cabazitaxel). In some embodiments, the composition comprises a carrier. In some embodiments, the carrier is anhydrous and/or hydrophobic. In other aspects, the carrier is aqueous based. In some embodiments, the taxane(s) is a plurality of nanoparticles of the taxane(s). In other embodiments, the taxane(s) is solubilized. Suitable compositions for use in the methods of the invention are disclosed in international patent publication WO 2017/049083 (application number PCT/US2016/052133), herein incorporated by reference. In a preferred embodiment, the composition is a hydrophobic composition comprising a continuous hydrophobic carrier, one or more volatile silicone fluids, and a plurality of taxane nanoparticles, wherein the taxane nanoparticles are suspended within the composition and wherein the mean particle size (number) of the taxane nanoparticles is from 0.1 microns to 1.5 microns. In some embodiments, the concentration of the one or more volatile silicone fluids is 5 to 24% w/w. In some embodiments, the composition does not contain volatile C₁-C₄ aliphatic alcohols or C₁-C₅ aliphatic alcohols. In some embodiments, the concentration of the taxane nanoparticles is at a concentration effective to provide a therapeutic improvement in the skin malignancy. In some embodiments, the concentration of the taxane nanoparticles is at a concentration of about 0.1 to about 2% w/w, or about 0.15 to about 2% w/w, or 0.1 to 5% w/w. In some embodiments, the method does not include additional skin-directed therapies, such as electrochemotherapy (ECT), photodynamic therapy (PDT), radiotherapy (RT), or intralesional therapy (ILT).

In some embodiments, the cutaneous metastasis is from one or more of the of the following cancers: breast, lung, nasal sinus, larynx, oral cavity, colorectal, stomach, ovary, testis, bladder, prostate, cervical, vaginal, thyroid, endometrial, kidney, esophagus, pancreas, liver, melanoma, and Kaposi's sarcoma (including AIDS-related Kaposi's sarcoma). In some embodiments, the skin cancer is melanoma, basal cell carcinoma, and/or squamous cell carcinoma.

I. Compositions

In one aspect of the invention, the compositions of the present invention are hydrophobic and comprise a continuous hydrophobic carrier, one or more volatile silicone fluids (such as cyclomethicone), and a plurality of taxane nanoparticles. The compositions can be suspensions of a plurality of the taxane nanoparticles within a mixture of the hydrophobic carrier and the volatile silicone fluid. The taxane nanoparticles can be completely dispersed, or partially dispersed and partially dissolved in the compositions. In various embodiments, the taxane nanoparticles are not completely dissolved in the compositions. The hydrophobic compositions can be anhydrous. A hydrophobic composition is a composition in which the total amount of the hydrophobic constituents in the composition is greater than the total amount of the non-hydrophobic constituents in the composition. The hydrophobic carrier can be the continuous phase of the hydrophobic compositions. Therefore, the compositions of the present invention can include at least two phases, a continuous hydrophobic carrier phase and a suspended taxane nanoparticle phase. The volatile silicone fluid can be solubilized and/or dispersed within the continuous phase.

Surprisingly, the hydrophobic compositions of the invention that include volatile silicone fluids at low concentrations, i.e., less than 25% w/w, in combination with a continuous, anhydrous hydrophobic carrier, exhibited greater skin penetration (i.e., penetration into the epidermal and/or dermal portions of the skin) of taxane nanoparticles as compared to the skin penetration of taxane nanoparticles from the hydrophobic carrier alone. In fact, and even more surprising, the addition of other skin penetration enhancers had little or no effect on the skin penetration of these compositions. Notably, however, the taxane nanoparticles did not penetrate through the skin (i.e., transdermal penetration) or only a negligible amount penetrated transdermally through the skin, i.e. less than 0.01 μg/cm². Furthermore, the skin penetration (i.e., epidermal or dermal penetration) of taxane nanoparticles from the anhydrous hydrophobic compositions was far superior to the skin penetration of taxane nanoparticles from aqueous based compositions even though the aqueous based compositions contained a skin penetration enhancer. Additionally, and also surprisingly, the hydrophobic compositions of the invention that include less than 25% of a volatile silicone fluid in combination with a hydrophobic carrier, do not need to contain alcohols, additional volatile solvents, additional penetration enhancers, or surfactants to provide enhanced skin penetration, thereby allowing for a most cost-efficient and simplified composition that can have reduced skin irritancy when topically applied. If desired, however, such components can be included in the compositions of the present invention. In some embodiments, the hydrophobic compositions are free of/do not include or contain additional penetration enhancers. In some embodiments, the hydrophobic compositions are free of/do not include or contain laurocapram. In some embodiments, the hydrophobic compositions are free of/do not include diethylene glycol monoethyl ether (DGME). In some embodiments, the hydrophobic compositions are free of/do not include isopropyl myristate. In other embodiments, the hydrophobic compositions are free of/do not include alpha tocopherol. In other embodiments, the hydrophobic compositions are free of/do not include or contain additional volatile solvents or compounds. In some embodiments, the hydrophobic compositions are free of/do not include or contain any alcohols or C₁-C₄ aliphatic alcohols. In some embodiments, the hydrophobic compositions are free of/do not include or contain alcohol or C₁-C₅ aliphatic alcohols. In other embodiments, the hydrophobic compositions are free of/do not include or contain surfactants. In other embodiments, the hydrophobic compositions are free of/do not include polymers/copolymers (or biodegradable polymers/copolymers). In other embodiments, the hydrophobic compositions are free of/do not include poloxamers, styrene-isobutylene-styrene (SIBS), a polyanhydride copolymer, polycaprolactone, polyethylene glycol, Poly (bis(P-carboxyphenoxy)propane-sebacic acid, and/or poly(D, L lactic-co-glycolic acid (PLGA). In various embodiments, the volatile silicone fluid is a cyclomethicone. In other embodiments, the cyclomethicone is cyclopentasiloxane. In some embodiments, the hydrophobic compositions are semi-solid compositions. In other embodiments the hydrophobic compositions are ointments. In some embodiments, the hydrophobic compositions are not sprays and are not sprayable.

In some embodiments, the hydrophobic compositions are semi-solid compositions, including ointments, and have a viscosity of from 12,500 cps to 247,500 cps, or from 25,000 cps to 150,000 cps as measured at room temperature by a Brookfield RV viscometer using a small sample adapter with a SC4-14 spindle and a 6R chamber at 5 rpm with an equilibration time of 2 minutes. An alternative method for performing viscosity measurements of the hydrophobic, semi-solid compositions is using a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds. In some embodiments, the hydrophobic compositions are semi-solid compositions, including ointments, and have a viscosity of from 25,000 cps to 500,000 cps, or from 25,000 cps to 400,000 cps, or from 25,000 cps to 350,000 cps, or from 25,000 cps to 300,000 cps, or from 50,000 cps to 500,000 cps, or from 50,000 cps to 400,000 cps, or from 50,000 cps to 350,000 cps, or from 50,000 cps to 300,000 cps, or from 75,000 cps to 500,000 cps, or from 75,000 cps to 400,000 cps, or from 75,000 cps to 350,000 cps, or from 75,000 cps to 300,000 cps, or from 100,000 cps to 500,000 cps, or from 100,000 cps to 400,000 cps, or from 100,000 cps to 350,000 cps, or from 100,000 cps to 300,000 cps using a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds.

In another aspect, the invention relates to compositions that inhibit crystal growth of taxane nanoparticles in carriers. In some embodiments, inhibition of crystal growth of taxane nanoparticles in carriers is accomplished by inclusion of the nanoparticles in a hydrophobic carrier. In some embodiments, the hydrophobic carriers comprise a hydrocarbon. In some embodiments, the hydrophobic carriers comprise petrolatum, mineral oil, and/or paraffin. In some embodiments, the mineral oil is heavy mineral oil. In other embodiments, the hydrophobic carriers further comprise one or more volatile silicone fluids. In still other embodiments, the volatile silicone fluid is cyclomethicone. In other embodiments, the cyclomethicone is cyclopentasiloxane. In other embodiments, inhibition of crystal growth of taxane nanoparticles in aqueous carriers is accomplished by inclusion of the nanoparticles in an aqueous carrier comprising poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer, or mixtures thereof.

The compositions of the present invention can be formulated in various forms suitable for pharmaceutical and topical delivery. Non-limiting examples include semi-solid compositions, lotions, liquid suspensions, emulsions, creams, gels, ointments, pastes, aerosol sprays, aerosol foams, non-aerosol sprays, non-aerosol foams, films, and sheets. Semi-solid compositions include ointments, pastes, and creams. For purposes of this invention, semi-solid compositions are not sprayable. The compositions can be impregnated in gauzes, bandages, or other skin dressing materials. In some embodiments, the compositions are semi-solid compositions. In some embodiments, the compositions are ointments. In other embodiments, the compositions are gels. In still other embodiments, the compositions are liquid suspensions. In some embodiments, the compositions are not sprays and are not sprayable.

The compositions of the present invention can be packaged in any package configuration suitable for topical products. Non-limiting examples include bottles, bottles with pumps, tottles, tubes (aluminum, plastic or laminated), jars, non-aerosol pump sprayers, aerosol containers, pouches, and packets. The packages can be configured for single-dose or multiple-dose administration.

In various embodiments, the compositions of the invention are hydrophobic. In other embodiments, the hydrophobic compositions are anhydrous. In various embodiments, the hydrophobic carriers are non-polar and/or non-volatile. In still other embodiments, the compositions are aqueous based. In other embodiments, the compositions of the invention are sterile. In other embodiments, the hydrophobic compositions are non-sterile. In other embodiments, the hydrophobic compositions have a low bioburden. In various embodiments, the hydrophobic compositions of the invention do not contain additional skin penetration enhancers. In other embodiments, the hydrophobic compositions of the invention do not contain additional volatile solvents. In still other embodiments, the hydrophobic compositions of the invention do not contain surfactants. In other embodiments, the hydrophobic compositions of the invention do not contain alcohols, C₁-C₄ aliphatic alcohols, or C₁-C₅ aliphatic alcohols.

A. Taxane Nanoparticles

Taxanes are poorly water soluble drugs having a solubility of less than or equal to 10 mg/mL in water at room temperature. Taxanes are widely used as chemotherapy agents. The term “taxanes” as used herein include paclitaxel (I), docetaxel (II), cabazitaxel (III), and/or any other taxane derivatives.

The taxane nanoparticles can be paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles, or nanoparticles of other taxane derivatives. Paclitaxel and docetaxel active pharmaceutical ingredients (APIs) are commercially available from Phyton Biotech LLC, Vancouver, Canada. The docetaxel API and nanoparticles contain not less than 90%, or not less than 95%, or not less than 97.5% docetaxel calculated on the anhydrous, solvent-free basis. The paclitaxel API and nanoparticles contain not less than 90%, or not less than 95%, or not less than 97% paclitaxel calculated on the anhydrous, solvent-free basis. Paclitaxel API and nanoparticles can be prepared from a semisynthetic chemical process or from a natural source such as plant cell fermentation or extraction. Paclitaxel is also sometimes referred to by the trade name TAXOL, although this is a misnomer because TAXOL is the trade name of a solution of paclitaxel in polyoxyethylated castor oil and ethanol intended for dilution with a suitable parenteral fluid prior to intravenous infusion. Paclitaxel is a poorly water soluble drug. The solubility of paclitaxel in water is less than 0.05 ppm as determined experimentally by the solubility method described in Example 1. The taxane nanoparticles can be in a crystalline form or in an amorphous form or a combination of both.

In various embodiments of the present invention, the taxane or paclitaxel nanoparticles are uncoated (neat) individual particles; the taxane or paclitaxel nanoparticles are not bound to any substance; no substances are absorbed or adsorbed onto the surface of the taxane or paclitaxel nanoparticles; the taxane or paclitaxel nanoparticles are not encapsulated in any substance; the taxane or paclitaxel nanoparticles are not coated with any substance; the taxane or paclitaxel nanoparticles are not microemulsions, nanoemulsions, microspheres, or liposomes of a taxane or paclitaxel; the taxane or paclitaxel particles are not bound to, encapsulated in, or coated with a monomer, a polymer (or biocompatible polymer), a protein, a surfactant, or albumin; and/or a monomer, a polymer (or biocompatible polymer), a protein, a surfactant, or albumin is not absorbed or adsorbed onto the surface of the taxane or paclitaxel nanoparticles. In some embodiments, the compositions are free of/do not include or contain a polymer or biocompatible polymer. In some embodiments, the compositions are free of/do not include or contain a protein. In some aspects of the invention, the compositions are free of/do not include or contain albumin. In some aspects of the invention, the compositions are free of/do not include or contain hyaluronic acid. In some aspects of the invention, the compositions are free of/do not include or contain a conjugate of hyaluronic acid and a taxane. In some aspects of the invention, the compositions are free of/do not include or contain a conjugate of hyaluronic acid and paclitaxel. In some aspects of the invention, the compositions are free of/do not include or contain poloxamers, styrene-isobutylene-styrene (SIBS), a polyanhydride copolymer, polycaprolactone, polyethylene glycol, Poly (bis(P-carboxyphenoxy)propane-sebacic acid, and/or poly(D, L lactic-co-glycolic acid (PLGA).

The taxane nanoparticles, including paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles, can have a mean particle size (number) of from 0.01 microns to 1.5 microns, or from 0.01 microns to 1.2 microns, or from 0.01 microns to 1 micron, or from 0.01 microns to less than 1 micron, or from 0.01 microns to 0.9 microns, or from 0.01 microns to 0.8 microns, or from 0.01 microns to 0.7 microns, or from 0.1 microns to 1.5 microns, or from 0.1 microns to 1.2 microns, or from 0.1 microns to 1 micron, or from 0.1 microns to less than 1 micron, or from 0.1 microns to 0.9 microns, or from 0.1 microns to 0.8 microns, or from 0.1 to 0.7 microns, or from 0.2 microns to 1.5 microns, or from 0.2 microns to 1.2 microns, or from 0.2 microns to 1 micron, or from 0.2 microns to less than 1 micron, or from 0.2 microns to 0.9 microns, or from 0.2 microns to 0.8 microns, or from 0.2 microns to 0.7 microns, or from 0.3 microns to 1.5 microns, or from 0.3 microns to 1.2 microns, or from 0.3 microns to 1 micron, or from 0.3 microns to less than 1 micron, or from 0.3 microns to 0.9 microns, or from 0.3 microns to 0.8 microns, or from 0.3 microns to 0.7 microns, or from 0.4 microns to 1.5 microns, or from 0.4 microns to 1.2 microns, or from 0.4 microns to 1 micron, or from 0.4 microns to less than 1 micron, or from 0.4 microns to 0.9 microns, or from 0.4 microns to 0.8 microns, or from 0.4 microns to 0.7 microns, or from 0.5 microns to 1.5 microns, or from 0.5 microns to 1.2 microns, or from 0.5 microns to 1 micron, or from 0.5 microns to less than 1 micron, or from 0.5 microns to 0.9 microns, or from 0.5 microns to 0.8 microns, or form 0.5 microns to 0.7 microns, or from 0.6 microns to 1.5 microns, or from 0.6 microns to 1.2 microns, or from 0.6 microns to 1 micron, or from 0.6 microns to less than 1 micron, or from 0.6 microns to 0.9 microns, or from 0.6 microns to 0.8 microns, or from 0.6 microns to 0.7 microns.

The particle size of the taxane when incorporated in a composition is determined by a particle size analyzer instrument and the measurement is expressed as the mean diameter based on a number distribution. A suitable particle size analyzer instrument is one which employs the analytical technique of light obscuration, also referred to as photozone or single particle optical sensing (SPOS). A suitable light obscuration particle size analyzer instrument is the ACCUSIZER available from Particle Sizing Systems, Port Richey, Fla.

In various embodiments, the mean particle size of the taxane nanoparticles incorporated in a composition does not grow larger than 20% of the initial mean particle size when the composition is stored at room temperature for at least 1 month, or for at least 3 months, or for at least 6 months or for at least 12 months. The term “initial mean particle size”, as used herein with regard to the particle size of taxane nanoparticles, is the mean particle size of the taxane incorporated in the composition when measured by a particle size analyzer instrument within 45 days after the completion of manufacture of the composition (date of manufacture), and the initial mean particle size is from 0.1 microns to 1.5 microns (number) or from 0.01 microns to 1.5 microns (number).

Nanoparticles of taxanes can be manufactured using various particle size-reduction methods and equipment known in the art. Such methods include, but are not limited to, wet or dry milling, micronizing, disintegrating, pulverizing, and supercritical carbon dioxide particle size reduction methods. In various embodiments, the taxane or paclitaxel nanoparticles are made by a supercritical carbon dioxide particle reduction method (also known as “precipitation with compressed anti-solvents” or “PCA”) as disclosed in US patents U.S. Pat. Nos. 5,874,029, 5,833,891, 6,113,795, 7,744,923, 8,778,181, US publication 2014/0296140, US publication 2016/0354336, US publication 2016/0374953, and international patent application publication WO 2016/197091 (application no. PCT/US16/35993) all of which are herein incorporated by reference.

In the supercritical carbon dioxide particle size reduction method, supercritical carbon dioxide (anti-solvent) and solvent, e.g. acetone or ethanol, are employed to generate uncoated taxane nanoparticles within a well-characterized particle-size distribution. The carbon dioxide and acetone are removed during processing (up to 0.5% residual solvent may remain), leaving taxane nanoparticle powder generally ranging in size from about 200 nm to about 800 nm. Stability studies show that the powder is stable in a vial dose form when stored at controlled room temperature (25° C./60% relative humidity) for up to 59 months and under accelerated conditions (40° C./75% relative humidity) for up to six months.

Taxane nanoparticles produced by various supercritical carbon dioxide particle size reduction methods can have unique physical characteristics as compared to taxane nanoparticles produced by conventional particle size reduction methods using physical impacting or grinding, e.g., wet or dry milling, micronizing, disintegrating, comminuting, microfluidizing, or pulverizing. As disclosed in US publication 2016/0354336 and international patent application publication WO 2016/197091 all of which are herein incorporated by reference, such unique characteristics include a bulk density (not tapped) between 0.05 g/cm³ and 0.15 g/cm³ and a specific surface area (SSA) of at least 18 m²/g of taxane (paclitaxel and docetaxel) nanoparticles, which are produced by the supercritical carbon dioxide particle size reduction methods described in US publication 2016/0354336 and international patent application publication WO 2016/197091 and as described below. This bulk density range is generally lower than the bulk density of taxane particles produced by conventional means, and the SSA is generally higher than the SSA of taxane particles produced by conventional means. These unique characteristics result in significant increases in dissolution rates in water/methanol media as compared to taxanes produced by conventional means. As used herein, the “specific surface area (SSA)” is the total surface area of the taxane nanoparticle per unit of taxane mass as measured by the Brunauer-Emmett-Teller (“BET”) isotherm by the following method: a known mass between 200 and 300 mg of the analyte is added to a 30 mL sample tube. The loaded tube is then mounted to a Porous Materials Inc. SORPTOMETER®, model BET-202A. The automated test is then carried out using the BETWIN® software package and the surface area of each sample is subsequently calculated. The bulk density measurement can be conducted by pouring the taxane nanoparticles into a graduated cylinder without tapping at room temperature, measuring the mass and volume, and calculating the bulk density.

As disclosed in US publication 2016/0354336 and international patent application publication WO 2016/197091, studies showed a SSA of 15.0 m²/g and a bulk density of 0.31 g/cm³ for paclitaxel nanoparticles produced by milling paclitaxel in a Deco-PBM-V-0.41 ball mill suing a 5 mm ball size, at 600 RPM for 60 minutes at room temperature. Also disclosed in US publication 2016/0354336 and international patent application publication WO 2016/197091, one lot of paclitaxel nanoparticles had a SSA of 37.7 m²/g and a bulk density of 0.085 g/cm³ when produced by a supercritical carbon dioxide method using the following method: a solution of 65 mg/ml of paclitaxel was prepared in acetone. A BETE MicroWhirl® fog nozzle (BETE Fog Nozzle, Inc.) and a sonic probe (Qsonica, model number Q700) were positioned in the crystallization chamber approximately 8 mm apart. A stainless steel mesh filter with approximately 100 nm holes was attached to the crystallization chamber to collect the precipitated paclitaxel nanoparticles. The supercritical carbon dioxide was placed in the crystallization chamber of the manufacturing equipment and brought to approximately 1200 psi at about 38° C. and a flow rate of 24 kg/hour. The sonic probe was adjusted to 60% of total output power at a frequency of 20 kHz. The acetone solution containing the paclitaxel was pumped through the nozzle at a flow rate of 4.5 mL/minute for approximately 36 hours. Additional lots of paclitaxel nanoparticles produced by the supercritical carbon dioxide method described above had SSA values of: 22.27 m²/g, 23.90 m²/g, 26.19 m²/g, 30.02 m²/g, 31.16 m²/g, 31.70 m²/g, 32.59 m²/g, 33.82 m²/g, 35.90 m²/g, 38.22 m²/g, and 38.52 m²/g.

As disclosed in US publication 2016/0354336 and international patent application publication WO 2016/197091, studies showed a SSA of 15.2 m²/g and a bulk density of 0.44 g/cm³ for docetaxel nanoparticles produced by milling docetaxel in a Deco-PBM-V-0.41 ball mill suing a 5 mm ball size, at 600 RPM for 60 minutes at room temperature. Also disclosed in US publication 2016/0354336 and international patent application publication WO 2016/197091, docetaxel nanoparticles had a SSA of 44.2 m²/g and a bulk density of 0.079 g/cm³ when produced by a supercritical carbon dioxide method using the following method: A solution of 79.32 mg/ml of docetaxel was prepared in ethanol. The nozzle and a sonic probe were positioned in the pressurizable chamber approximately 9 mm apart. A stainless steel mesh filter with approximately 100 nm holes was attached to the pressurizable chamber to collect the precipitated docetaxel nanoparticles. The supercritical carbon dioxide was placed in the pressurizable chamber of the manufacturing equipment and brought to approximately 1200 psi at about 38° C. and a flow rate of 68 slpm. The sonic probe was adjusted to 60% of total output power at a frequency of 20 kHz. The ethanol solution containing the docetaxel was pumped through the nozzle at a flow rate of 2 mL/minute for approximately 95 minutes). The precipitated docetaxel agglomerates and particles were then collected from the supercritical carbon dioxide as the mixture is pumped through the stainless steel mesh filter. The filter containing the nanoparticles of docetaxel was opened and the resulting product was collected from the filter.

As disclosed in US publication 2016/0354336 and international patent application publication WO 2016/197091, dissolution studies showed an increased dissolution rate in methanol/water media of paclitaxel and docetaxel nanoparticles made by the supercritical carbon dioxide methods described in US publication 2016/0354336 and international patent application publication WO 2016/197091 as compared to paclitaxel and docetaxel nanoparticles made by milling paclitaxel and docetaxel using a Deco-PBM-V-0.41 ball mill suing a 5 mm ball size, at 600 RPM for 60 minutes at room temperature. The procedures used to determine the dissolution rates are as follows. For paclitaxel, approximately 50 mg of material were coated on approximately 1.5 grams of 1 mm glass beads by tumbling the material and beads in a vial for approximately 1 hour. Beads were transferred to a stainless steel mesh container and placed in the dissolution bath containing methanol/water 50/50 (v/v) media at 37° C., pH 7, and a USP Apparatus II (Paddle), operating at 75 rpm. At 10, 20, 30, 60, and 90 minutes, a 5 mL aliquot was removed, filtered through a 0.22 μm filter and analyzed on a UV/VIS spectrophotometer at 227 nm. Absorbance values of the samples were compared to those of standard solutions prepared in dissolution media to determine the amount of material dissolved. For docetaxel, approximately 50 mg of material was placed directly in the dissolution bath containing methanol/water 15/85 (v/v) media at 37° C., pH 7, and a USP Apparatus II (Paddle), operating at 75 rpm. At 5, 15, 30, 60, 120 and 225 minutes, a 5 mL aliquot was removed, filtered through a 0.22 μm filter, and analyzed on a UV/VIS spectrophotometer at 232 nm. Absorbance values of the samples were compared to those of standard solutions prepared in dissolution media to determine the amount of material dissolved. For paclitaxel, the dissolution rate was 47% dissolved in 30 minutes for the nanoparticles made by the supercritical carbon dioxide method versus 32% dissolved in 30 minutes for the nanoparticles made by milling. For docetaxel, the dissolution rate was 27% dissolved in 30 minutes for the nanoparticles made by the supercritical carbon dioxide method versus 9% dissolved in 30 minutes for the nanoparticles made by milling.

In some embodiments, the paclitaxel nanoparticles have an SSA of at least 18, at least 19, at least 20, at least 21, at least 22, at least 23, at least 24, at least 25, at least 26, at least 27, at least 28, at least 29, at least 30, at least 31, at least 32, at least 33, at least 34, or at least 35 m²/g. In other embodiments, the paclitaxel nanoparticles have an SSA of 18 m²/g to 50 m²/g, or 20 m²/g to 50 m²/g, or 22 m²/g to 50 m²/g, or 25 m²/g to 50 m²/g, or 30 m²/g to 50 m²/g, or 18 m²/g to 45 m²/g, or 20 m²/g to 45 m²/g, or 22 m²/g to 45 m²/g, or 25 m²/g to 45 m²/g, or 30 m²/g to 45 m²/g, or 18 m²/g to 40 m²/g, or 20 m²/g to 40 m²/g, or 22 m²/g to 40 m²/g, or 25 m²/g to 40 m²/g, or 30 m²/g to 40 m²/g.

In some embodiments, the paclitaxel nanoparticles have a bulk density (not-tapped) of 0.05 g/cm³ to 0.15 g/cm³, or 0.05 g/cm³ to 0.20 g/cm³.

In some embodiments, the paclitaxel nanoparticles have a dissolution rate of at least 40% w/w dissolved in 30 minutes or less in a solution of 50% methanol/50% water (v/v) in a USP II paddle apparatus operating at 75 RPM, at 37° C., and at a pH of 7.

In some embodiments, the docetaxel nanoparticles have an SSA of at least 18, at least 19, at least 20, at least 21, at least 22, at least 23, at least 24, at least 25, at least 26, at least 27, at least 28, at least 29, at least 30, at least 31, at least 32, at least 33, at least 34, at least 35, at least 36, at least 37, at least 38, at least 39, at least 40, at least 41, or at least 42 m²/g. In other embodiments, the docetaxel nanoparticles have an SSA of 18 m²/g to 60 m²/g, or 22 m²/g to 60 m²/g, or 25 m²/g to 60 m²/g, or 30 m²/g to 60 m²/g, or 40 m²/g to 60 m²/g, or 18 m²/g to 50 m²/g, or 22 m²/g to 50 m²/g, or 25 m²/g to 50 m²/g, or 30 m²/g to 50 m²/g, or 40 m²/g to 50 m²/g.

In some embodiments, the docetaxel nanoparticles have a bulk density (not-tapped) of 0.05 g/cm³ to 0.15 g/cm³.

In some embodiments, the docetaxel nanoparticles have a dissolution rate of at least 20% w/w dissolved in 30 minutes or less in a solution of 15% methanol/85% water (v/v) in a USP II paddle apparatus operating at 75 RPM, at 37° C., and at a pH of 7.

It was found that paclitaxel nanoparticle crystals have a tendency to grow in suspensions of water or saline solutions over time forming large needle-like crystals. A crystal growth study was conducted and the results are shown in Table 2 in Example 2 below. It was found that the nanoparticles crystals did not grow in the hydrophobic materials. Also, and surprisingly, the nanoparticle crystals did not grow in aqueous solutions of benzalkonium chloride, CARBOPOL ULTREZ 10, or poloxamer 407.

B. Hydrophobic Carriers

The hydrophobic carriers of the present invention can comprise substances from plant, animal, paraffinic, and/or synthetically derived sources. Hydrophobic substances are generally known as substances that lack an affinity for and repel water. The hydrophobic carrier can be the continuous phase of the compositions. In various embodiments, the hydrophobic carriers are non-polar and/or non-volatile. Non-limiting examples include fats, butters, greases, waxes, solvents, and oils; mineral oils; vegetable oils; petrolatums; water insoluble organic esters and triglycerides; and fluorinated compounds. The hydrophobic carriers can also comprise silicone materials. Silicone materials are defined as compounds based on polydialkylsiloxanes and include polymers, elastomers (crosslinked silicones), and adhesives (branched silicones). Non-limiting examples of silicone materials include dimethicone (polydimethylsiloxane), dimethicone copolyol, cyclomethicone, simethicone, silicone elastomers such as ST-elastomer 10 (DOW CORNING), silicone oils, silicone polymers, volatile silicone fluids, and silicone waxes. In some embodiments, the hydrophobic carrier does not comprise silicone materials.

Plant derived materials include, but are not limited to, arachis (peanut) oil, balsam Peru oil, carnauba wax, candellila wax, castor oil, hydrogenated castor oil, cocoa butter, coconut oil, corn oil, cotton seed oil, jojoba oil, macadamia seed oil, olive oil, orange oil, orange wax, palm kernel oil, rapeseed oil, safflower oil, sesame seed oil, shea butter, soybean oil, sunflower seed oil, tea tree oil, vegetable oil, and hydrogenated vegetable oil.

Non-limiting examples of animal derived materials include beeswax (yellow wax and white wax), cod liver oil, emu oil, lard, mink oil, shark liver oil, squalane, squalene, and tallow. Non-limiting examples of paraffinic materials include isoparaffin, microcrystalline wax, heavy mineral oil, light mineral oil, ozokerite, petrolatum, white petrolatum, and paraffin wax.

Non-limiting examples of organic esters and triglycerides include C₁₂-15 alkyl benzoate, isopropyl myristate, isopropyl palmitate, medium chain triglycerides, mono- and di-glycerides, trilaurin, and trihydroxystearin.

A non-limiting example of a fluorinated compound is perfluoropolyether (PFPE), such as FOMBLIN®HC04 commercially available from Solvay Specialty Polymers.

The hydrophobic carriers of the present invention can comprise pharmaceutical grade hydrophobic substances. In various embodiments of the present invention the hydrophobic carriers comprise petrolatum, mineral oil, or paraffin, or mixtures thereof. In some embodiments, the mineral oil is heavy mineral oil.

In some embodiments, the concentration of the hydrophobic carrier in the compositions is greater than 10% w/w of the total composition weight. In other embodiments, the concentration of the hydrophobic carrier in the compositions is greater than 15%, or greater than 20%, or greater than 25%, or greater than 30%, or greater than 35%, or greater than 40%, or greater than 45%, or greater than 50%, or greater than 55%, or greater than 60%, or greater than 65%, or greater than 70%, or greater than 75%, or greater than 80%, or greater than 82%, or greater than 85%, or greater than 87%, or greater than 90% w/w of the total composition weight. In other embodiments, the concentration of the hydrophobic carrier in the compositions is from greater than 10% w/w to 95% w/w of the total composition weight. In other embodiments, the concentration of the hydrophobic carrier in the compositions is from 11% w/w to 95% w/w, or from 12% w/w to 95% w/w, or from 13% w/w to 95% w/w, or from 14% w/w to 95% w/w, or from 15% w/w to 95% w/w, or from 16% w/w to 95% w/w, or from 17% w/w to 95% w/w, or from 18% w/w to 95% w/w, or from 19% w/w to 95% w/w, or from 20% w/w to 95% w/w of the total composition weight.

(i) Petrolatum

Petrolatum is a purified mixture of semi-solid saturated hydrocarbons obtained from petroleum, and varies from dark amber to light yellow in color. White petrolatum is wholly or nearly decolorized and varies from cream to snow white in color. Petrolatums are available with different melting point, viscosity, and consistency characteristics. Petrolatums may also contain a stabilizer such as an antioxidant. Pharmaceutical grades of petrolatum include Petrolatum USP and White Petrolatum USP.

Various petrolatums are available commercially from the Penreco Corporation under the trade names: ULTIMA, SUPER, SNOW, REGENT, LILY, CREAM, ROYAL, BLOND, and AMBER. Various grades of petrolatum are also available commercially from the Sonneborn Corporation under the trade names: ALBA, SUPER WHITE PROTOPET, SUPER WHITE FONOLINE, WHITE PROTOPET 1S, WHITE PROTOPET 2L, WHITE PROTOPET 3C, WHITE FONOLINE, PERFECTA, YELLOW PROTOPET 2A, YELLOW FONOLINE, PROTOLINE, SONOJELL #4, SONOJELL #9, MINERAL JELLY #10, MINERAL JELLY #14, MINERAL JELLY #17, AND CARNATION TROUGH GREASE. Petrolatums are also available from the Spectrum Chemical Mfg. Corp.

(ii) Mineral Oil

Mineral oil is a mixture of liquid hydrocarbons obtained from petroleum. Mineral oil is available in various viscosity grades, such as light mineral oil, heavy mineral oil, and extra heavy mineral oil. Light mineral oil has a kinematic viscosity of not more than 33.5 centistokes at 40° C. Heavy mineral oil has a kinematic viscosity of not less than 34.5 centistokes at 40° C. Mineral oil may contain a suitable stabilizer. Pharmaceutical grades of mineral oil include Mineral Oil USP, which is heavy mineral oil, and Light Mineral Oil NF, which is light mineral oil. Mineral oil is commercially available from the Penreco Corporation under the DRAKEOL trade name, and the Sonneborn Corporation under the trade names BENOL, BLANDOL, BRITOL, CARNATION, ERVOL, GLORIA, KAYDOL, KLEAROL, PROTOL, and RUDOL. Mineral oil is also commercially available from the Spectrum Chemical Mfg. Corp.

(iii) Paraffin Wax

Paraffin wax is a purified mixture of solid hydrocarbons obtained from petroleum. It may also be synthetically derived by the Fischer-Tropsch process from carbon monoxide and hydrogen which are catalytically converted to a mixture of paraffin hydrocarbons. Paraffin wax may contain an antioxidant. Pharmaceutical grades of paraffin wax include Paraffin NF and Synthetic Paraffin NF. Paraffin waxes are commercially available from the Spectrum Chemical Mfg. Corp, Koster Keunen, Inc. and Frank B. Ross, Inc.

C. Volatile Silicone Fluids

Volatile silicone fluids, also known as volatile silicone oils, are volatile liquid polysiloxanes which can by cyclic or linear. They are liquid at room temperature. Volatile silicone fluids are hydrophobic materials. Linear volatile silicone fluids include polydimethylsiloxane, hexamethyldisiloxane and octamethyltrisiloxane and are commercially available from Dow Corning under the trade names DOW CORNING Q7-9180 Silicone Fluid 0.65 cSt and DOW CORNING Q7-9180 Silicone Fluid 1.0 cSt, respectively. Cyclic volatile silicone fluids are generally known as cyclomethicones.

(i) Cyclomethicone

Cyclomethicone is a fully methylated cyclic siloxane containing repeating units of formula (IV): [—(CH₃)₂SiO—]_(n)  (IV) in which n is 3, 4, 5, 6, or 7; or mixtures thereof. Cyclomethicone is a clear, colorless volatile liquid silicone fluid. Cyclomethicone has emollient properties and helps to improve the tactile feel of an oil based product by making it feel less greasy on the skin. Pharmaceutical grade cyclomethicone includes Cyclomethicone NF. Cyclomethicone NF is represented by formula (IV) in which n is 4 (cyclotetrasiloxane), 5 (cyclopentasiloxane), or 6 (cyclohexasiloxane); or mixtures thereof. Cyclopentasiloxane, also known as decamethylcylcopentasiloxane, cyclomethicone D5, or cyclomethicone 5, is the cyclomethicone represented by formula (IV) in which n is 5 (pentamer), but it can contain small amounts (generally less than 1%) of one or more of the other cyclic chain length cyclomethicones. Cyclopentasiloxane is available in a pharmaceutical grade as Cyclomethicone NF. Cyclomethicones are commercially available from Dow Corning under the trade names DOW CORNING ST-Cyclomethicone 5-NF, DOW CORNING ST-Cyclomethicone 56-NF, and XIAMETER PMX-0245. It is also commercially available from the Spectrum Chemical Mfg. Corp. Cyclopentasiloxane has a vapor pressure of about 20 to about 27 Pa at 25° C.

In one embodiment, the concentration of cyclomethicone in the composition is less than 25% w/w. In another embodiment, the cyclomethicone in the composition is at a concentration from 5 to 24% w/w. In another embodiment, the concentration of cyclomethicone is from 5 to 20% w/w. In another embodiment, the cyclomethicone is at a concentration of from 5 to 18% w/w. In another embodiment, the concentration of cyclomethicone is 13% w/w. In various embodiments, the concentration of cyclomethicone can be 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, or 24% w/w or any percentage derivable therein of the total composition weight. In one embodiment, the cyclomethicone is cyclopentasiloxane.

D. Aqueous Based Compositions

Aqueous based compositions of the invention comprise taxane nanoparticles and an aqueous carrier. The aqueous formulations are dispersions (suspensions) of the taxane nanoparticles in an aqueous carrier. The taxane nanoparticles can be completely dispersed, partially dispersed and partially dissolved, but not completely dissolved in the aqueous carrier. An aqueous based composition is a composition in which water is the major constituent. Aqueous carriers can include single phase aqueous solutions, and multi-phase aqueous based emulsions such oil-in-water and water-in-oil emulsions.

It was observed that taxane nanoparticle crystals, such as paclitaxel nanoparticles, rapidly grew in water and in aqueous based carriers. In many cases, the growth was observed in as little as 3 days at room temperature, and some cases in 24 hours. Many of the crystals were needle-like in shape and were larger than 5 μm in length. A study was conducted and the results are shown in Table 2 in Example 2. Surprisingly, the taxane nanoparticle crystal growth was inhibited by the addition of poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer to the aqueous based carrier during processing. The addition of poloxamer 188 did not inhibit the growth of the nanoparticle crystals.

It was also observed that the presence of a quaternary ammonium compound, or a cross-linked acrylic acid polymer, or mixtures thereof in an aqueous carrier comprising taxane nanoparticle crystals prevented growth of the nanoparticle crystals over time. A study was conducted and the results are shown in Table 11 in Example 8 revealing that the mean particle size of poorly water soluble taxane nanoparticles (paclitaxel) in an aqueous composition comprising poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer, or mixtures thereof does not grow larger than 20% of the initial mean particle size when the aqueous composition is stored at room temperature for 6 months. In some embodiments, there is disclosed an aqueous based composition comprising an aqueous carrier; a plurality of taxane nanoparticles; and a quaternary ammonium compound, or a cross-linked acrylic acid polymer, or mixtures thereof; wherein the mean particle size of the taxane nanoparticles is from 0.1 microns to 1.5 microns (number) or from 0.01 microns to 1.5 microns (number), and wherein the mean particle size of the taxane nanoparticles does not grow larger than 20% of the initial mean particle size when the composition is stored at room temperature for at least 6 months. In other embodiments, the composition further comprises poloxamer 407.

In one aspect of the invention, disclosed are compositions comprising taxane nanoparticles, an aqueous carrier, and poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer, or mixtures thereof. It was surprisingly found that the addition of poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer inhibited the crystal growth of the taxane nanoparticles in aqueous carriers. The aqueous based compositions of the invention are suitable for topical, injectable, (IV) infusion, or oral liquid dosage forms. In one embodiment, the additive to inhibit crystal growth is poloxamer 407. In various embodiments, the quaternary ammonium compound is the additive to inhibit crystal growth and is benzalkonium chloride or benzethonium chloride. In other embodiments, the quaternary ammonium compound is benzalkonium chloride. In other embodiments, the cross-linked acrylic acid polymer is the additive to inhibit crystal growth and is Carbomer.

In one aspect of the invention, the composition comprises poloxamer 407 and taxane nanoparticles in an aqueous carrier suitable for injection delivery including (IV) infusion. In various embodiments, the taxane nanoparticles are docetaxel nanoparticles, paclitaxel nanoparticles, or cabazitaxel nanoparticles.

In another aspect of the invention, the composition comprises a quaternary ammonium compound and taxane nanoparticles in an aqueous carrier suitable for injection delivery including (IV) infusion. In various embodiments, the taxane nanoparticles are docetaxel nanoparticles, paclitaxel nanoparticles, or cabazitaxel nanoparticles. In other embodiments, the quaternary ammonium compounds are benzalkonium chloride or benzethonium chloride.

In one aspect of the invention, disclosed are methods of inhibiting the growth of a dispersion of crystalline taxane nanoparticles in an aqueous based carrier, the method comprising adding poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer, or mixtures thereof, to the aqueous based carrier during processing, wherein the mean particle size of the taxane nanoparticles is from 0.1 microns to 1.5 microns (number) or from 0.01 microns to 1.5 microns (number). In some embodiments, the quaternary ammonium compound is benzalkonium chloride or benzethonium chloride. In some embodiments, the cross-linked acrylic acid polymer is carbomer. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles. In still other embodiments, the taxane nanoparticles are paclitaxel nanoparticles.

(i) Poloxamer 407

Poloxamer 407 is a solid, hydrophilic, nonionic, synthetic block copolymer of ethylene oxide and propylene oxide conforming to the general formula (V) HO(C₂H₄O)_(a)(C₃H₆O)_(b)(C₂H₄O)_(aH)  (V) where a is 101 and b is 56. Poloxamer 407 has an average molecular weight of 9840-14600. The term “poloxamer” is the nonproprietary name of the copolymer. Poloxamers are available in several types which have various physical forms and various average molecular weights. Each specific poloxamer type is identified by the nonproprietary name “poloxamer” followed by a three digit number, the first two digits of which when multiplied by 100 correspond to the approximate average molecular weight of the polyoxypropylene portion of the copolymer; and the third digit, when multiplied by 10, corresponds to the percentage by weight of the polyoxyethylene portion. Poloxamers are available in pharmaceutical, cosmetic, and industrial grades. Pharmaceutical grade poloxamers are listed in recognized pharmaceutical compendia such as USP/NF and European Pharmacopeia (PhEur). According to the USP/NF and PhEur, a suitable antioxidant may be added. Poloxamer 407 is commercially available from BASF under the trade name PLURONIC® F127. The addition of poloxamer 188 to an aqueous carrier did not inhibit crystal growth of the taxane nanoparticles. Suitable concentrations of Poloxamer 407 are at least 2% w/w, or from 0.1 to 25% w/w, or from 0.1 to 20% w/w, or from 0.1 to 15% w/w, or from 0.1 to 10% w/w, or from 1 to 25% w/w, or from 1 to 20% w/w, or from 1 to 15% w/w, or from 1 to 10% w/w, or from 2 to 25% w/w, or from 2 to 20% w/w, or from 2 to 15% w/w, or from 2 to 10% w/w.

(ii) Quaternary Ammonium Compounds

Quaternary ammonium compounds (including salts) are positively charged tetra-substituted nitrogen derivatives of formula (VI)

in which R′, R², R³, and R⁴ may be the same or different, but may not be hydrogen. X⁻ represents a typical anion such as chloride. Suitable quaternary ammonium compounds include benzalkonium chloride and benzethonium chloride. Benzalkonium chloride is commercially available in a 100% powder or a 50% aqueous solution. Other examples of quaternary ammonium compounds are disclosed in the International Cosmetic Ingredient Dictionary and Handbook, 12th edition, 2008 herein incorporated by reference. Suitable concentrations of quaternary ammonium compounds are at least 0.05% w/w, or at least 0.1% w/w, or at least 1% w/w, or at least 2% w/w, or from 0.05 to 5% w/w, or from 0.1 to 5% w/w, or from 1 to 5% w/w, or from 2 to 5% w/w.

(iii) Cross-Linked Acrylic Acid Polymers

Cross-linked acrylic acid polymers are high molecular weight homo- and co-polymers of acrylic acid cross-linked with a polyalkenyl polyether. Suitable cross-linked acrylic acid polymers include Carbomer (INCI name), Acrylates Copolymer (INCI name), Acrylates/C10-30 Alkyl Acrylate Crosspolymer (INCI name), Acrylates Crosspolymer-4 (INCI name), and Polyacrylate-1 Crosspolymer (INCI name). The above mentioned polymers are all commercially available from the Lubrizol Corporation under the CARBOPOL® trade name. Examples of Carbomer available from the Lubrizol Corporation include CARBOPOL 934, CARBOPOL 934P, CARBOPOL 940, CARBOPOL 980, CARBOPOL 941, CARBOPOL 981, CARBOPOL 2984, CARBOPOL 5984, CARBOPOL SILK 100, CARBOPOL ETD 2050, ULTREZ 10, and ULTREZ 30. Examples of Acrylates Copolymer available from the Lubrizol Corporation include CARBOPOL AQUA SF-1, and CARBOPOL AQUA SF-1 OS. Examples of Acrylates/C10-30 Alkyl Acrylate Crosspolymer available from the Lubrizol Corporation include CARBOPOL ULTREZ 20, CARBOPOL ULTREZ 21, CARBOPOL ETD 2020, CARBOPOL 1342, CARBOPOL 1382, and CARBOPOL SC-200. An example of Acrylates Crosspolymer-4 is CARBOPOL AQUA SF-2. An example of Polyacrylate-1 Crosspolymer is CARBOPOL AQUA CC. Suitable concentrations of cross-linked acrylic acid polymers are at least 0.1% w/w, or 0.5% w/w, or from 0.1 to 5% w/w, or from 0.5 to 5% w/w.

E. Additional Ingredients and Adjuvants

The compositions of the invention can further comprise functional ingredients suitable for use in pharmaceutical compositions. Non-limiting examples include absorbents, acidifying agents, antimicrobial agents, antioxidants, binders, biocides, buffering agents, bulking agents, crystal growth inhibitors, chelating agents, colorants, deodorant agents, emulsion stabilizers, film formers, fragrances, humectants, lytic agents, enzymatic agents, opacifying agents, oxidizing agents, pH adjusters, plasticizers, preservatives, reducing agents, emollient skin conditioning agents, humectant skin conditioning agents, moisturizers, surfactants, emulsifying agents, cleansing agents, foaming agents, hydrotopes, solvents, suspending agents, viscosity control agents (rheology modifiers), viscosity increasing agents (thickeners), and propellants. Listings and monographs of the examples of the functional ingredients described herein are disclosed in The International Cosmetic Ingredient Dictionary and Handbook (INCI), 12^(th) Edition, 2008, herein incorporated by reference.

The compositions of the invention can further comprise additional pharmaceutically active ingredients, cosmetically active ingredients, and veterinary agents suitable for topical use.

Although, the hydrophobic compositions of the present invention can further comprise additional penetration enhancers, it was found that it was not necessary to include additional penetration enhancers to increase the skin penetration (i.e., into the epidermal and dermal portions of skin) of the taxane nanoparticles in hydrophobic compositions comprising a hydrophobic carrier and one or more volatile silicone fluids. In fact, the additions of skin penetration enhancers had little or no effect on the skin penetration of the hydrophobic compositions.

The term “penetration enhancer” has been used to describe compounds or materials or substances that facilitate drug absorption through the skin. These compounds or materials or substances can have a direct effect on the permeability of the skin, or they can augment percutaneous absorption by increasing the thermodynamic activity of the penetrant, thereby increasing the effective escaping tendency and concentration gradient of the diffusing species. The predominant effect of these enhancers is to either increase the stratum corneum's degree of hydration or disrupt its lipoprotein matrix, the net result in either case being a decrease in resistance to drug (penetrant) diffusion (Remington, The Science and Practice of Pharmacy, 22^(nd) ed.).

Non-limiting examples of skin penetration enhancers include oleyl alcohol, isopropyl myristate, dimethyl isosorbide (DMI) available under the tradename ARLASOLVE DMI, and Diethylene Glycol Monoethyl Ether (DGME) which is available under the trade name TRANSCUTOL P. Other examples of skin penetration enhancers can be found in “Skin Penetration Enhancers Cited in the Technical Literature”, Osborne, David W., and Henke, Jill J., Pharmaceutical Technology, November 1997, herein incorporated by reference. Such examples include: Fatty alcohols such as aliphatic alcohols, Decanol, Lauryl alcohol (dodecanol), Linolenyl alcohol, Nerolidol, 1-Nonanol, n-Octanol, Oleyl alcohol, Fatty acid esters, Butylacetate, Cetyl lactate, Decyl N,N-dimethylamino acetate, Decyl N,N-dimethylamino isopropionate, Diethyleneglycol oleate, Diethyl sebacate, Diethyl succinate, Diisopropyl sebacate, Dodecyl N,N-dimethylamino acetate, Dodecyl (N,N-dimethylamino)-butyrate, Dodecyl N,N-dimethylamino isopropionate, Dodecyl 2-(dimethylamino) propionate, EO-5-oleyl ester, Ethyl acetate, Ethylaceto acetate, Ethyl propionate, Glycerol monoethers, Glycerol monolaurate, Glycerol monooleate, Glycerol monolinoleate, Isopropyl isostearate, Isopropyl linoleate, Isopropyl myristate, Isopropyl myristate/fatty acid monoglyceride combination, Isopropyl myristate/ethanol/L-lactic acid (87:10:3) combination, Isopropyl palmitate, Methyl acetate, Methyl caprate, Methyl laurate, Methyl propionate, Methyl valerate, 1-Monocaproyl glycerol, Monoglycerides (medium chain length), Nicotinic esters (benzyl), Octyl acetate, Octyl N,N-dimethylamino acetate, Oleyl oleate, n-Pentyl N-acetylprolinate, Propylene glycol monolaurate, Sorbitan dilaurate, Sorbitan dioleate, Sorbitan monolaurate, Sorbitan monooleates, Sorbitan trilaurate, Sorbitan trioleate, Sucrose coconut fatty ester mixtures, Sucrose monolaurate, Sucrose monooleate, and Tetradecyl N,N-dimethylamino acetate; Fatty acids such as Alkanoic acids, Capric acid, Diacid, Ethyloctadecanoic acid, Hexanoic acid, Lactic acid, Lauric acid, Linoelaidic acid, Linoleic acid, Linolenic acid, Neodecanoic acid, Oleic acid, Palmitic acid, Pelargonic acid, Propionic acid, and Vaccenic acid; Fatty alcohol ethers such as α-Monoglyceryl ether, EO-2-oleyl ether, EO-5-oleyl ether, EO-10-oleyl ether, and Ether derivatives of polyglycerols and alcohols (1-O-dodecyl-3-O-methyl-2-O-(2′, 3′-dihydroxypropyl) glycerol); Biologics such as L-α-amino-acids, Lecithin, Phospholipids, Saponin/phospholipids, Sodium deoxycholate, Sodium taurocholate, and Sodium tauroglycocholate; Enzymes such as Acid phosphatase, Calonase, Orgelase, Papain, Phospholipase A-2, Phospholipase C, and Triacylglycerol hydrolase; Amines and Amides such as Acetamide derivatives, Acyclic amides, N-Adamantyl n-alkanamides, Clofibric acid amides, N,N-Didodecyl acetamide, Di-2-ethylhexylamine, Diethyl methyl benzamide, N,N-Diethyl-m-toluamide, N,N-Dimethyl-m-toluarnide, Ethomeen S12 [bis-(2-hydroxyethyl) oleylamine], Hexamethylene lauramide, Lauryl-amine (dodecylamine), Octyl amide, Oleylamine, Unsaturated cyclic ureas, and Urea; Complexing Agents such as, β- and γ-cyclodextrin complexes, Hydroxypropyl methylcellulose, Liposomes, Naphthalene diamide diimide, and Naphthalene diester diimide; Macrocyclics such as Macrocyclic lactones, ketones, and anhydrides (optimum ring-16), and Unsaturated cyclic ureas; Classical surfactants such as Brij 30, Brij 35, Brij 36T, Brij 52, Brij 56, Brij 58, Brij 72, Brij 76, Brij 78, Brij 92, Brij 96, Brij 98, Cetyl trimethyl ammonium bromide, Empicol ML26/F, HCO-60 surfactant, Hydroxypolyethoxydodecane, Ionic surfactants (ROONa, ROSO₃Na, RNH₃Cl, R=8-16), Lauroyl sarcosine, Nonionic surface active agents, Nonoxynol, Octoxynol, Phenylsulfonate CA, Pluronic F68, Pluronic F 127, Pluronic L62, Polyoleates (nonionic surfactants), Rewopal HV 10, Sodium laurate, Sodium Lauryl sulfate (sodium dodecyl sulfate), Sodium oleate, Sorbitan dilaurate, Sorbitan dioleate, Sorbitan monolaurate, Sorbitan monooleates, Sorbitan trilaurate, Sorbitan trioleate, Span 20, Span 40, Span 85, Synperonic NP, Triton X-100, Tween 20, Tween 40, Tween 60, Tween 80, and Tween 85; N-methyl pyrrolidone and related compounds such as N-Cyclohexyl-2-pyrrolidone, 1-Butyl-3-dodecyl-2-pyrrolidone, 1,3-Dimethyl-2-imidazolikinone, 1,5 Dimethyl-2-pyrrolidone, 4,4-Dimethyl-2-undecyl-2-oxazoline, 1-Ethyl-2-pyrrolidone, 1-Hexyl-4-methyloxycarbonyl-2-pyrrolidone, 1-Hexyl-2-pyrrolidone, 1-(2-Hydroxyethyl) pyrrolidinone, 3-Hydroxy-N-methyl-2-pyrrolidinone, 1-Isopropyl-2-undecyl-2-imidazoline, 1-Lauryl-4-methyloxycarbonyl-2-pyrrolidone, N-Methyl-2-pyrrolidone, Poly(N-vinylpyrrolidone), Pyroglutamic acid esters, and 2-Pyrrolidone (2-pyrrolidinone); Ionic compounds such as Ascorbate, Amphoteric cations and anions, Calcium thioglycolate, Cetyl trimethyl ammonium bromide, 3,5-Diiodosalicylate sodium, Lauroylcholine iodide, 5-Methoxysalicylate sodium, Monoalkyl phosphates, 2-PAM chloride, 4-PAM chloride (derivatives of N-methyl picolinium chloride), Sodium carboxylate, and Sodium hyaluronate; Dimethyl sulfoxide and related compounds such as Cyclic sulfoxides, Decylmethyl sulfoxide, Dimethyl sulfoxide (DMSO), and 2-Hydroxyundecyl methyl sulfoxide; Solvents and related compounds such as Acetone, n-Alkanes (chain length between 7 and 16), Cyclohexyl-1,1-dimethylethanol, Dimethylacetamide, Dimethyl formamide, Ethanol, Ethanol/d-limonene combination, 2-Ethyl-1,3-hexanediol, Ethoxydiglycol (TRANSCUTOL), Glycerol, Glycols, Lauryl chloride, Limonene, N-Methylformamide, 2-Phenylethanol, 3-Phenyl-1-propanol, 3-Phenyl-2-propen-1-ol, Polyethylene glycol, Polyoxyethylene sorbitan monoesters, Polypropylene glycol, Primary alcohols (tridecanol), Propylene glycol, Squalene, Triacetin, Trichloroethanol, Trifluoroethanol, Trimethylene glycol, and Xylene; Azone and related compounds such as N-Acyl-hexahydro-2-oxo-1H-azepines, N-Alkyl-dihydro-1,4-oxazepine-5,7-diones, N-Alkylmorpholine-2,3-diones, N-Alkylmorpholine-3,5-diones, Azacyclo alkane derivatives (-ketone, -thione), Azacycloalkenone derivatives, 1-[2-(Decylthio)ethyl]azacyclopentan-2-one (HPE-101), N-(2,2-Dihydroxyethyl)dodecylamine, 1-Dodecanoylhexahydro-1-H-azepine, 1-Dodecyl azacycloheptan-2-one (AZONE or laurocapram), N-Dodecyl diethanolamine, N-Dodecyl-hexahydro-2-thio-1H-azepine, N-Dodecyl-N-(2-methoxyethyl)acetamide, N-Dodecyl-N-(2-methoxyethyl) isobutyramide, N-Dodecyl-piperidine-2-thione, N-Dodecyl-2-piperidinone, N-Dodecyl pyrrolidine-3,5-dione, N-Dodecyl pyrrolidine-2-thione, N-Dodecyl-2-pyrrolidone, 1-Famesylazacycloheptan-2-one, 1-Famesylazacyclopentan-2-one, 1-Geranylazacycloheptan-2-one, 1-Geranylazacyclopentan-2-one, Hexahydro-2-oxo-azepine-1-acetic acid esters, N-(2-Hydroxyethyl)-2-pyrrolidone, 1-Laurylazacycloheptane, 2-(1-Nonyl)-1,3-dioxolane, 1-N-Octylazacyclopentan-2-one, N-(1-Oxododecyl)-hexahydro-1H-azepine, N-(1-Oxododecyl)-morpholines, 1-Oxohydrocarbyl-substituted azacyclohexanes, N-(1-Oxotetradecyl)-hexahydro-2-oxo-1 H-azepine, and N-(1-Thiododecyl)-morpholines; and others such as Aliphatic thiols, Alkyl N,N-dialkyl-substituted amino acetates, Anise oil, Anticholinergic agent pretreatment, Ascaridole, Biphasic group derivatives, Bisabolol, Cardamom oil, 1-Carvone, Chenopodium (70% ascaridole), Chenopodium oil, 1,8 Cineole (eucalyptol), Cod liver oil (fatty acid extract), 4-Decyloxazolidin-2-one, Dicyclohexylmethylamine oxide, Diethyl hexadecylphosphonate, Diethyl hexadecylphosphoramidate, N,N-Dimethyl dodecylamine-N-oxide, 4, 4-Dimethyl-2-undecyl-2-oxazoline, N-Dodecanoyl-L-amino acid methyl esters, 1,3-Dioxacycloalkanes (SEPAs), Dithiothreitol, Eucalyptol (cineole), Eucalyptus oil, Eugenol, Herbal extracts, Lactam N-acetic acid esters, N-Hydroxyethalaceamide, N-Hydroxyethylacetamide, 2-Hydroxy-3-oleoyloxy-1-pyroglutamyloxypropane, Menthol, Menthone, Morpholine derivatives, N-Oxide, Nerolidol, Octyl-β-D-(thio)glucopyranosides, Oxazolidinones, Piperazine derivatives, Polar lipids, Polydimethylsiloxanes, Poly [2-(methylsulfinyl)ethyl acrylate], Polyrotaxanes, Polyvinylbenzyldimethylalkylammonium chloride, Poly(N-vinyl-N-methyl acetamide), Sodium pyroglutaminate, Terpenes and azacyclo ring compounds, Vitamin E (α-tocopherol), Vitamin E TPGS and Ylang-ylang oil. Additional examples of penetration enhancers not listed above can be found in “Handbook of Pharmaceutical Excipients”, Fifth edition, and include glycofurol, lanolin, light mineral oil, myristic acid, polyoxyethylene alky ethers, and thymol. Other examples of penetration enhancers include ethanolamine, diethanolamine, triethanolamine, diethylene glycol, monoethyl ether, citric acid, succinic acid, borage oil, tetrahydropiperine (THP), methanol, ethanol, propanol, octanol, benzyl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, and polyethylene glycol monolaurate.

Although the hydrophobic compositions of the invention can further comprise alcohols, it is not necessary for the compositions to contain alcohols, C₁-C₄ aliphatic alcohols, or C₁-C₅ aliphatic alcohols. In some aspects of the invention, the compositions are free of/do not include or contain C₁-C₄ aliphatic alcohols, or C₁-C₅ aliphatic alcohols.

Although the hydrophobic compositions of the invention can further comprise additional volatile solvents, it is not necessary for the hydrophobic compositions to contain additional volatile solvents. Volatile solvents are also known as “fugitive” solvents. Non-limiting examples of volatile solvents include volatile alcohols, such as C₁ to C₄ aliphatic alcohols; and volatile C₁ to C₄ aliphatic ketones, such as acetone. In some aspects of the inventions, the compositions are free of/do not include or contain volatile C₁ to C₄ aliphatic ketones. In some aspects of the inventions, the compositions are free of/do not include or contain volatile C₁ to C₄ aliphatic alcohols.

Although the hydrophobic compositions of the invention can further comprise surfactants, it is not necessary for the hydrophobic compositions to contain surfactants. The term “surfactant” or “surface active agent” means a compound or material or substance that exhibits the ability to lower the surface tension of water or to reduce the interfacial tension between two immiscible substances and includes anionic, cationic, nonionic, amphoteric, and/or phospholipid surfactants. Non-limiting examples of surfactants can be found in McCutcheon's Emulsifiers & Detergents, 2001 North American Edition herein incorporated by reference and also in the International Cosmetic Ingredient Dictionary and Handbook (INCI), 12th Edition, 2008, herein incorporated by reference. Such examples include, but are not limited to, the following: block polymers, e.g., Poloxamer 124; ethoxylated alcohols e.g., Ceteth-2, Ceteareth-20, Laureth-3; ethoxylated fatty esters and oils, e.g., PEG-40 Hydrogenated Castor Oil, PEG-36 Castor Oil, PEG-150 Distearate; glycerol esters, e.g., Polyglyceryl-3 Diisostearate, Glyceryl Stearate; glycol esters, PEG-12 Dioleate, LEXEMUL P; phosphate esters, e.g., Cetyl Phosphate; polymeric surfactants, e.g., PVM/MA Copolymer, Acrylates/C₁₀-30 Alkyl Acrylate Crosspolymer; quaternary surfactants, e.g., Cetrimonium Chloride; Silicone Based Surfactants, e.g., PEG/PPG-20/6 Dimethicone; Sorbitan Derivatives, e.g., Sorbitan Stearate, Polysorbate 80; sucrose and glucose esters and derivatives, e.g., PEG-20 Methyl Glucose Sesquistearate; and sulfates of alcohols, e.g., Sodium Lauryl Sulfate. More generally, surfactants can be classified by their ionic type such as anionic, cationic, nonionic, or amphoteric. They can also be classified by their chemical structures, such as block polymers, ethoxylated alcohols, ethoxylated fatty esters and oils, glycerol esters, glycol esters, phosphate esters, polymeric surfactants, quaternary surfactants, silicone-based surfactants, sorbitan derivatives, sucrose and glucose esters and derivatives, and sulfates of alcohols.

F. Manufacture

The compositions of the invention may be manufactured by methods and equipment known in the art for manufacture of pharmaceutical products including topical, injectable, and oral liquid products. Such methods include, but are not limited to the use of mechanical mixers, dissolvers, dispersers, homogenizers, and mills. Non-limiting examples include LIGHTNIN propeller mixers, COWLES dissolvers, IKA ULTRA TURRAX dispersers, SILVERSON homogenizers, LEE counter-rotating side-scraping mixers, in-line and in-tank rotor-stator homogenizers, 3-roll mills, ointment mills, and rotor-stator mills. “All-in-one” vacuum mixing systems that have a rotating side-scraping mixer plus an in-tank homogenizer may also be used. Such mixers include, but are not limited to OLSA mixers, FRYMA-KORUMA mixers, and LEE TRI-MIX TURBO-SHEAR kettles. The compositions of the invention can be manufactured from small laboratory scale batches using laboratory mixing equipment to full-scale production batches.

II. Enhanced Topical Delivery Methods

In one aspect of the invention, there is disclosed a method for enhancing penetration of taxane nanoparticles into a skin malignancy, including a skin cancer and/or a cutaneous metastasis, the method comprising applying to the affected area of the skin malignancy the topical compositions disclosed herein. In a preferred embodiment, the method comprises applying to the affected area of the skin malignancy a hydrophobic composition which comprises a hydrophobic carrier, one or more volatile silicone fluids, and a plurality of taxane nanoparticles. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles. In some embodiments, the taxane nanoparticles, including paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles, have a mean particle size (number) of from 0.01 microns to 1.5 microns, or from 0.01 microns to 1.2 microns, or from 0.01 microns to 1 micron, or from 0.01 microns to less than 1 micron, or from 0.01 microns to 0.9 microns, or from 0.01 microns to 0.8 microns, or from 0.01 microns to 0.7 microns, or from 0.1 microns to 1.5 microns, or from 0.1 microns to 1.2 microns, or from 0.1 microns to 1 micron, or from 0.1 microns to less than 1 micron, or from 0.1 microns to 0.9 microns, or from 0.1 microns to 0.8 microns, or from 0.1 to 0.7 microns, or from 0.2 microns to 1.5 microns, or from 0.2 microns to 1.2 microns, or from 0.2 microns to 1 micron, or from 0.2 microns to less than 1 micron, or from 0.2 microns to 0.9 microns, or from 0.2 microns to 0.8 microns, or from 0.2 microns to 0.7 microns, or from 0.3 microns to 1.5 microns, or from 0.3 microns to 1.2 microns, or from 0.3 microns to 1 micron, or from 0.3 microns to less than 1 micron, or from 0.3 microns to 0.9 microns, or from 0.3 microns to 0.8 microns, or from 0.3 microns to 0.7 microns, or from 0.4 microns to 1.5 microns, or from 0.4 microns to 1.2 microns, or from 0.4 microns to 1 micron, or from 0.4 microns to less than 1 micron, or from 0.4 microns to 0.9 microns, or from 0.4 microns to 0.8 microns, or from 0.4 microns to 0.7 microns, or from 0.5 microns to 1.5 microns, or from 0.5 microns to 1.2 microns, or from 0.5 microns to 1 micron, or from 0.5 microns to less than 1 micron, or from 0.5 microns to 0.9 microns, or from 0.5 microns to 0.8 microns, or form 0.5 microns to 0.7 microns, or from 0.6 microns to 1.5 microns, or from 0.6 microns to 1.2 microns, or from 0.6 microns to 1 micron, or from 0.6 microns to less than 1 micron, or from 0.6 microns to 0.9 microns, or from 0.6 microns to 0.8 microns, or from 0.6 microns to 0.7 microns. In other embodiments, the taxane nanoparticles are paclitaxel nanoparticles. In some embodiments, the paclitaxel nanoparticles have an SSA of at least 18, at least 19, at least 20, at least 21, at least 22, at least 23, at least 24, at least 25, at least 26, at least 27, at least 28, at least 29, at least 30, at least 31, at least 32, at least 33, at least 34, or at least 35 m²/g. In other embodiments, the paclitaxel nanoparticles have an SSA of 18 m²/g to 50 m²/g, or 20 m²/g to 50 m²/g, or 22 m²/g to 50 m²/g, or 25 m²/g to 50 m²/g, or 30 m²/g to 50 m²/g, or 18 m²/g to 45 m²/g, or 20 m²/g to 45 m²/g, or 22 m²/g to 45 m²/g, or 25 m²/g to 45 m²/g, or 30 m²/g to 45 m²/g, or 18 m²/g to 40 m²/g, or 20 m²/g to 40 m²/g, or 22 m²/g to 40 m²/g, or 25 m²/g to 40 m²/g, or 30 m²/g to 40 m²/g. In some embodiments, the paclitaxel nanoparticles have a bulk density (not-tapped) of 0.05 g/cm³ to 0.15 g/cm³, or 0.05 g/cm³ to 0.20 g/cm³. In various embodiments, the hydrophobic carriers are non-polar and/or non-volatile. In some embodiments, the hydrophobic carriers comprise a hydrocarbon. In other embodiments, the hydrophobic carriers comprise petrolatum, mineral oil, and paraffin. In some embodiments, the mineral oil is heavy mineral oil. In some embodiments, the concentration of the volatile silicone fluid in the composition formulation is at an amount effective to enhance skin penetration of the taxane nanoparticles as compared to the formulation without the volatile silicone fluid. A suitable method for measuring penetration into a skin malignancy can be by use of an in vitro Franz diffusion cell (FDC) system using human cadaver skin. A suitable in vitro Franz diffusion cell system is described in Example 9 below. In some embodiments, the one or more volatile silicone fluid is at a concentration from 5 to 24% w/w. In other embodiments, the concentration of the one or more volatile silicone fluid is from 5 to 20% w/w. In other embodiments, the one or more volatile silicone fluid is at a concentration of from 5 to 18% w/w. In still other embodiments, the concentration of the one or more volatile silicone fluid is 13% w/w. In various embodiments, the concentration of the one or more volatile silicone fluid can be 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, or 24% w/w or any percentage derivable therein of the total composition weight. In various embodiments, the one or more volatile silicone fluid is cyclomethicone. In other embodiments, the cyclomethicone is cyclopentasiloxane. In some embodiments, the hydrophobic compositions do not contain additional penetration enhancers. In other embodiments, the hydrophobic compositions do not contain additional volatile solvents. In still other embodiments, the hydrophobic compositions do not contain a surfactant. In other embodiments, the hydrophobic compositions are free of/do not include or contain alcohols, or C₁ to C₄ aliphatic alcohols, or C₁ to C₅ aliphatic alcohols. In various embodiments, the taxane can be paclitaxel, docetaxel, or cabazitaxel. In some embodiments, the skin malignancy is a skin cancer and/or a cutaneous metastasis. In some embodiments, the hydrophobic compositions are anhydrous. In other embodiments, the hydrophobic compositions are sterile. In other embodiments, the hydrophobic compositions are non-sterile. In other embodiments, the hydrophobic compositions have a low bioburden. In some embodiments, the hydrophobic compositions are semi-solid compositions. In still other embodiments, the hydrophobic compositions are ointments. In some embodiments, the hydrophobic compositions are semi-solid compositions, including ointments, and have a viscosity of from 12,500 cps to 247,500 cps, or from 25,000 cps to 150,000 cps as measured at room temperature by a Brookfield RV viscometer using a small sample adapter with a SC4-14 spindle and a 6R chamber at 5 rpm with an equilibration time of 2 minutes. An alternative method for performing viscosity measurements of the hydrophobic, semi-solid compositions is using a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds. In some embodiments, the hydrophobic compositions are semi-solid compositions, including ointments, and have a viscosity of from 25,000 cps to 500,000 cps, or from 25,000 cps to 400,000 cps, or from 25,000 cps to 350,000 cps, or from 25,000 cps to 300,000 cps, or from 50,000 cps to 500,000 cps, or from 50,000 cps to 400,000 cps, or from 50,000 cps to 350,000 cps, or from 50,000 cps to 300,000 cps, or from 75,000 cps to 500,000 cps, or from 75,000 cps to 400,000 cps, or from 75,000 cps to 350,000 cps, or from 75,000 cps to 300,000 cps, or from 100,000 cps to 500,000 cps, or from 100,000 cps to 400,000 cps, or from 100,000 cps to 350,000 cps, or from 100,000 cps to 300,000 cps using a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds. In some embodiments, the hydrophobic compositions are not sprays and are not sprayable.

In another aspect of the inventions, disclosed is a method of enhancing penetration of taxane nanoparticles into a skin malignancy comprising topically applying a hydrophobic composition comprising a plurality of taxane nanoparticles to the surface of the skin malignancy, wherein the penetration of the taxane nanoparticles from the hydrophobic composition is greater than the penetration of taxane nanoparticles from a suspension of taxane nanoparticles in an aqueous based composition. A suitable method for determining penetration of taxane nanoparticles in a skin malignancy is by an in vitro Franz diffusion cell (FDC) system using human cadaver skin. A suitable in vitro Franz diffusion cell system is described in Example 9 below. In some embodiments, the taxane nanoparticles have a mean particle size (number) from 0.1 microns to 1.5 microns. In other embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles. In other embodiments, the hydrophobic composition further comprises a hydrophobic carrier. In other embodiments, the skin malignancy is a skin cancer or a cutaneous metastasis.

III. Methods for the Inhibition of Crystal Growth in Formulations

In one aspect of the invention, disclosed are methods of inhibiting the growth of crystalline taxane nanoparticles, the method comprising contacting the taxane nanoparticles with a hydrophobic carrier. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles. In other embodiments the composition is anhydrous. In other embodiments, the hydrophobic carriers comprise a hydrocarbon. In other embodiments, the hydrocarbon is petrolatum, mineral oil, or paraffin wax, or mixtures thereof. In some embodiments, the mineral oil is heavy mineral oil. In some embodiments, the compositions further comprises one or more volatile silicone fluids. In other embodiments, the volatile silicone fluid is cyclomethicone. In other embodiments, the cyclomethicone is cyclopentasiloxane.

In another aspect of the invention, disclosed are methods of inhibiting the growth of a dispersion of crystalline taxane nanoparticles in an aqueous based carrier, the method comprising adding poloxamer 407, a quaternary ammonium compound, or a cross-linked acrylic acid polymer to the aqueous based carrier at the time of manufacture. In some embodiments, the additive is poloxamer 407. In various embodiments, the quaternary ammonium compound is the additive and is benzalkonium chloride or benzethonium chloride. In some embodiments, the quaternary ammonium compound is benzalkonium chloride. In some embodiments, the cross-linked acrylic acid polymer is the additive and is Carbomer. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles.

IV. Topical Treatment of Skin Malignancies

The methods of the invention include methods of treatment of skin malignancies including skin cancers and cutaneous metastases in a patient by topically applying to the affected area (topical therapy) compositions disclosed herein comprising taxanes. The “affected area” of a skin malignancy can include at least a portion of the skin where the skin malignancy lesion (tumor) is visibly present on the outermost surface of the skin or directly underneath the surface of the skin (epithelial/dermal covering), and can include areas of the skin in the proximity of the skin malignancy likely to contain visibly undetectable preclinical lesions. In some embodiments, the taxane is paclitaxel. In other embodiments, the taxane is docetaxel or cabazitaxel. In some aspects, the compositions are hydrophobic and can comprise a hydrophobic carrier. In other aspects, the compositions are aqueous based compositions and can comprise an aqueous carrier. In some embodiments, the carrier is anhydrous. In some embodiments, the taxanes are a plurality of taxane nanoparticles. In some embodiments, the plurality of taxane nanoparticles are suspended within the compositions. In other aspects, the taxanes are solubilized in the compositions.

A preferred method for the topical treatment of a skin malignancy comprises topically administering to the affected area a hydrophobic composition comprising a continuous hydrophobic carrier, one or more volatile silicone fluids, and a plurality of taxane nanoparticles, wherein the taxane nanoparticles are suspended within the composition, wherein the mean particle size (number) of the taxane nanoparticles is from 0.1 microns to 1.5 microns or from 0.01 microns to 1.5 microns, and wherein the concentration of the taxane nanoparticles is at an amount effective to provide a therapeutic improvement in the condition of the skin malignancy. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles. In some embodiments, the taxane nanoparticles, including paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles have a mean particle size (number) of from 0.01 microns to 1.5 microns, or from 0.01 microns to 1.2 microns, or from 0.01 microns to 1 micron, or from 0.01 microns to less than 1 micron, or from 0.01 microns to 0.9 microns, or from 0.01 microns to 0.8 microns, or from 0.01 microns to 0.7 microns, or from 0.1 microns to 1.5 microns, or from 0.1 microns to 1.2 microns, or from 0.1 microns to 1 micron, or from 0.1 microns to less than 1 micron, or from 0.1 microns to 0.9 microns, or from 0.1 microns to 0.8 microns, or from 0.1 to 0.7 microns, or from 0.2 microns to 1.5 microns, or from 0.2 microns to 1.2 microns, or from 0.2 microns to 1 micron, or from 0.2 microns to less than 1 micron, or from 0.2 microns to 0.9 microns, or from 0.2 microns to 0.8 microns, or from 0.2 microns to 0.7 microns, or from 0.3 microns to 1.5 microns, or from 0.3 microns to 1.2 microns, or from 0.3 microns to 1 micron, or from 0.3 microns to less than 1 micron, or from 0.3 microns to 0.9 microns, or from 0.3 microns to 0.8 microns, or from 0.3 microns to 0.7 microns, or from 0.4 microns to 1.5 microns, or from 0.4 microns to 1.2 microns, or from 0.4 microns to 1 micron, or from 0.4 microns to less than 1 micron, or from 0.4 microns to 0.9 microns, or from 0.4 microns to 0.8 microns, or from 0.4 microns to 0.7 microns, or from 0.5 microns to 1.5 microns, or from 0.5 microns to 1.2 microns, or from 0.5 microns to 1 micron, or from 0.5 microns to less than 1 micron, or from 0.5 microns to 0.9 microns, or from 0.5 microns to 0.8 microns, or form 0.5 microns to 0.7 microns, or from 0.6 microns to 1.5 microns, or from 0.6 microns to 1.2 microns, or from 0.6 microns to 1 micron, or from 0.6 microns to less than 1 micron, or from 0.6 microns to 0.9 microns, or from 0.6 microns to 0.8 microns, or from 0.6 microns to 0.7 microns. In other embodiments, the taxane nanoparticles are paclitaxel nanoparticles. In some embodiments, the paclitaxel nanoparticles have an SSA of at least 18, at least 19, at least 20, at least 21, at least 22, at least 23, at least 24, at least 25, at least 26, at least 27, at least 28, at least 29, at least 30, at least 31, at least 32, at least 33, at least 34, or at least 35 m²/g. In other embodiments, the paclitaxel nanoparticles have an SSA of 18 m²/g to 50 m²/g, or 20 m²/g to 50 m²/g, or 22 m²/g to 50 m²/g, or 25 m²/g to 50 m²/g, or 30 m²/g to 50 m²/g, or 18 m²/g to 45 m²/g, or 20 m²/g to 45 m²/g, or 22 m²/g to 45 m²/g, or 25 m²/g to 45 m²/g, or 30 m²/g to 45 m²/g, or 18 m²/g to 40 m²/g, or 20 m²/g to 40 m²/g, or 22 m²/g to 40 m²/g, or 25 m²/g to 40 m²/g, or 30 m²/g to 40 m²/g. In some embodiments, the paclitaxel nanoparticles have a bulk density (not-tapped) of 0.05 g/cm³ to 0.15 g/cm³, or 0.05 g/cm³ to 0.20 g/cm³. In various embodiments, the hydrophobic carriers are non-polar and/or non-volatile. In some embodiments, the hydrophobic carriers comprise a hydrocarbon. In other embodiments, the hydrophobic carriers comprise petrolatum, mineral oil, and paraffin. In some embodiments, the mineral oil is heavy mineral oil. In some embodiments, the volatile silicone fluid is at a concentration of from 5 to 24% w/w. In other embodiments, the volatile silicone fluid is at a concentration of from 5 to 20% w/w. In other embodiments, the volatile silicone fluid is at a concentration of from 5 to 18% w/w. In other embodiments, the concentration of the volatile silicone fluid is 13% w/w. In some embodiments, the volatile silicone fluid is cyclomethicone. In other embodiments, the cyclomethicone is cyclopentasiloxane. In various embodiments, the hydrophobic compositions are free of/do not include or contain additional penetration enhancers. In some embodiments, the hydrophobic compositions are free of/do not include or contain laurocapram, and/or diethylene glycol monoethyl ether (DGME), and/or isopropyl myristate, and/or alpha tocopherol. In other embodiments, the hydrophobic compositions are free of/do not include or contain additional volatile solvents. In other embodiments, the hydrophobic compositions are free of/do not include or contain a surfactant. In other embodiments, the hydrophobic compositions are free of/do not include or contain alcohols, C₁-C₄ aliphatic alcohols, or C₁ to C₅ aliphatic alcohols. In some embodiments, the hydrophobic compositions comprise one or more volatile silicone fluids, but do not contain additional silicone materials. In some embodiments, the hydrophobic compositions are free of/do not include hyaluronic acid; and/or are free of/do not include a conjugate of hyaluronic acid and a taxane; and/or are free of/do not include a conjugate of hyaluronic acid and paclitaxel; and/or are free of/do not include a polymer or a biodegradeable polymer; and/or are free of/do not include a poloxamer, styrene-isobutylene-styrene (SIBS), a polyanhydride copolymer, polycaprolactone, polyethylene glycol, Poly (bis(P-carboxyphenoxy)propane-sebacic acid, and/or poly(D, L lactic-co-glycolic acid) (PLGA).

The concentration of the taxane nanoparticles is at an amount effective to provide a therapeutic improvement in the condition of the skin malignancy. This improvement can be indicated by visual observation and measurement of the affected area after treatment to include at least one of the following accomplishments: (a) a reduction of the size of the skin malignancy lesions (tumors); (b) a reduction of the number of the skin malignancy lesions (tumors); (c) elimination of the skin malignancy lesions (tumors); and (d) a reduction of pain at the site of the skin malignancy lesions (tumors). The concentration of the taxane nanoparticles can be from 0.05 to 10% w/w, or the concentration of the taxane nanoparticles can be from 0.05 to 5% w/w, or the concentration of the taxane nanoparticles can be from 0.1 to 5% w/w, or the concentration of the taxane nanoparticles can be 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1.0, 1.1, 1.2, 1.25, 1.3, 1.4, 1.5, 1.6, 1.7, 1.75, 1.8, 1.9, 2.0, 2.1, 2.2, 2.25, 2.3, 2.4, 2.5, 2.6, 2.7, 2.75, 2.8, 2.9, 3.0, 3.1, 3.2, 3.25, 3.3, 3.4, 3.5, 3.6, 3.7, 3.75, 3.8, 3.9, 4.0, 4.1, 4.2, 4.25, 4.3, 4.4, 4.5, 4.6, 4.7, 4.75, 4.8, 4.9, 5, 6, 7, 8, 9, or 10% w/w or any percentage derivable therein of the total composition weight. In some embodiments, the taxane nanoparticles are paclitaxel nanoparticles, docetaxel nanoparticles, or cabazitaxel nanoparticles. In other embodiments, the taxane nanoparticles are paclitaxel nanoparticles. In some embodiments, the paclitaxel nanoparticles are at a concentration of about 0.05 to less than 3% w/w, or about 0.05 to about 2% w/w, or about 0.05 to about 1% w/w, or about 0.05 to about 0.3% w/w, or about 0.05 to about 0.2% w/w, or about 0.05 to about 0.15% w/w, or about 0.1 to about 2% w/w, or about 0.1 to about 1% w/w, or about 0.1 to about 0.3% w/w, or about 0.1 to about 0.2% w/w, or about 0.15 to about 2% w/w, or about 0.15 to about 1% w/w, or about 0.15 to about 0.3% w/w, or about 0.3 to about 2% w/w, or about 0.3 to about 1% w/w, or about 1 to about 2% w/w, or about 0.2 to about 0.4% w/w, or about 0.5 to about 1.5% w/w, or about 1.5 to about 2.5% w/w in the compositions. In other embodiments, the concentration of the paclitaxel nanoparticles is 80 to 120% of 1% w/w (i.e., 0.8 to 1.2% w/w), or 80 to 120% of 0.05% w/w, or 80 to 120% of 0.1% w/w, or 80 to 120% of 0.15% w/w, or 80 to 120% of 0.2% w/w, or 80 to 120% of 0.25% w/w, or 80 to 120% of 0.3% w/w, or 80 to 120% of 0.35% w/w, or 80 to 120% of 0.4% w/w, or 80 to 120% of 0.45% w/w, or 80 to 120% of 0.5% w/w, or 80 to 120% of 0.55% w/w, or 80 to 120% of 0.6% w/w, or 80 to 120% of 0.65% w/w, or 80 to 120% of 0.7% w/w, or 80 to 120% of 0.75% w/w, or 80 to 120% of 0.8% w/w, or 80 to 120% of 0.85% w/w, or 80 to 120% of 0.9% w/w, or 80 to 120% of 0.95% w/w, or 80 to 120% of 1.5% w/w, or 80 to 120% of 2% w/w, or 80 to 120% of 2.5% w/w.

In some embodiments, the hydrophobic compositions are sterile. In other embodiments, the hydrophobic compositions are non-sterile. In other embodiments, the hydrophobic compositions have a low bioburden. In other embodiments, the hydrophobic compositions are anhydrous. In some embodiments, the hydrophobic compositions are semi-solid compositions. In still other embodiments, the hydrophobic compositions are ointments. In some embodiments, the hydrophobic compositions are semi-solid compositions, including ointments, and have a viscosity of from 12,500 cps to 247,500 cps, or from 25,000 cps to 150,000 cps as measured at room temperature by a Brookfield RV viscometer using a small sample adapter with a SC4-14 spindle and a 6R chamber at 5 rpm with an equilibration time of 2 minutes. An alternative method for performing viscosity measurements of the hydrophobic, semi-solid compositions is using a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds. In some embodiments, the hydrophobic compositions are semi-solid compositions, including ointments, and have a viscosity of from 25,000 cps to 500,000 cps, or from 25,000 cps to 400,000 cps, or from 25,000 cps to 350,000 cps, or from 25,000 cps to 300,000 cps, or from 50,000 cps to 500,000 cps, or from 50,000 cps to 400,000 cps, or from 50,000 cps to 350,000 cps, or from 50,000 cps to 300,000 cps, or from 75,000 cps to 500,000 cps, or from 75,000 cps to 400,000 cps, or from 75,000 cps to 350,000 cps, or from 75,000 cps to 300,000 cps, or from 100,000 cps to 500,000 cps, or from 100,000 cps to 400,000 cps, or from 100,000 cps to 350,000 cps, or from 100,000 cps to 300,000 cps using a Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds. In some embodiments, the hydrophobic compositions are not sprays and are not sprayable. In some embodiments, the compositions are not dry powders. In some embodiments, the compositions do not solely include the taxane nanoparticles.

In some embodiments, the skin malignancy is a skin cancer. The method of the invention can be used to treat a variety of skin cancers including, but not limited to melanoma, basal cell carcinoma, squamous cell carcinoma, and Kaposi's sarcoma (including AIDS related Kaposi's sarcoma). In other embodiments the skin malignancy is a cutaneous metastasis. The methods of the invention can be used to treat cutaneous metastases derived from a variety of primary cancers. The cutaneous metastasis can be from, but not limited to, one or more of the of the following primary malignancies: breast, lung, nasal, sinus, larynx, oral cavity, colon (large intestine), rectum, stomach, ovary, testis, bladder, prostate, cervical, vaginal, thyroid, endometrial, kidney, esophagus, pancreas, liver, melanoma, and Kaposi's sarcoma. In some embodiments, the cutaneous metastasis is from lung cancer, breast cancer, colon cancer, oral cancer, ovarian cancer, kidney cancer, esophageal cancer, stomach cancer, or liver cancer. In some embodiments, the cutaneous metastasis is from breast cancer. In some embodiments, the cutaneous metastasis is a non-melanoma cutaneous metastasis.

The amount of the hydrophobic composition topically applied to the affected area of the skin malignancy can vary depending on the size of the affected area and the concentration of the paclitaxel in the composition, but generally can be applied at approximately the thickness of a dime to fully cover the affected area. Another suitable method for determining the amount of composition to apply is the “Finger-Tip Unit” (FTU) approach. One FTU is the amount of topical composition that is squeezed out from a standard tube along an adult's fingertip (This assumes the tube has a standard 5 mm nozzle). A fingertip is from the very end of the finger to the first crease in the finger. The composition can be applied with a gloved hand or spatula or other means of topical administration. In some embodiments, the composition is applied to skin malignancies which have an intact skin covering (epithelial/dermal covering). In some embodiments, the composition is applied to ulcerated areas where the skin malignancy lesion is on the surface of the skin or where the skin covering is degraded and the skin malignancy lesion is exposed. In some embodiments, the composition is not applied to ulcerated areas. The affected area can be gently cleansed with water (and mild soap if required) and dried prior to application. Once the composition is applied, the application site can be covered with an occlusive dressing such as TEGADERM® or SOLOSITE®. The dosing of the composition can vary, but generally can include an application once, twice, or three times daily at approximately the same time each day until the condition is improved or eliminated. The therapeutic improvement of the condition of the skin malignancy as a result of the methods of treatment disclosed herein can be indicated by visual observation and measurement of the affected area after treatment to include at least one of the following accomplishments: (a) a reduction of the size of the skin malignancy lesions (tumors); (b) a reduction of the number of the skin malignancy lesions (tumors); (c) elimination of the skin malignancy lesions (tumors); and (d) a reduction of pain at the site of the skin malignancy lesions (tumors).

EXAMPLES

The present invention will be described in greater detail by way of specific examples. The following examples are offered for illustrative purposes only, and are not intended to limit the invention in any manner. Those of skill in the art will readily recognize a variety of noncritical parameters, which can be changed or modified to yield essentially the same results.

Example 1—Solubility of Paclitaxel in Various Solvents

The solubility of paclitaxel was determined in various solvents by the following method: (a) for each solvent, about 2 g of the solvent was weighed into a clear glass vial, (b) approximately 0.1 g of paclitaxel was added to each vial, (c) each vial was mixed with a stir bar on a magnetic stirrer for 2 hours at room temperature, (d) each vial was then checked every 1-2 hours to see if the solution became clear. If yes, an additional approximately 0.1 g of paclitaxel was added to the vial and mixing was continued. Step “d” was continued for each vial for a total of 48 hours.

The solution from each vial was measured for paclitaxel concentration using an HPLC method based on Agilent Technical Application Note for Paclitaxel “Analysis of Taxol by HPLC”, 2002, and modified to use a 227 nm detection wavelength, rather than 204 nm (the 227 nm wavelength is used in the USP paclitaxel monograph, and reduces the solvent effects seen at lower wavelengths).

The solubility values are shown in Table 1.

TABLE 1 Paclitaxel Solubility Solvent at RT Hexylene Glycol 4.07% w/w Diethylene Glycol Monoethyl Ether, 33.10% w/w NF (TRANSCUTOL P) Propylene Carbonate 4.74% w/w Super Refined Oleic Acid, NF 0.041% w/w Super Refined Oleyl Alcohol, NF 0.38% w/w Diisopropyl Adipate (CERAPHYE 230) 3.51% w/w Medium Chain Triglycerides, NF 0.32% w/w Propylene Glycol, USP 0.88% w/w Polyethylene Glycol 400, NF 22.30% w/w Benzyl Alcohol, NF 17.02% w/w Isopropyl Myristate, NF 0.048% w/w Mineral Oil, USP (heavy) 0.3 ppm Dimethyl Isosorbide 38.22% w/w Purified Water, USP <0.05 ppm

Example 2 Observations of Paclitaxel Nanoparticle Crystals in Various Substances and Solutions of Substances

Paclitaxel nanoparticles were dispersed in various substances and aqueous solutions of substances and observed for crystal growth. The results are shown in Table 2.

TABLE 2 Visual observation by light microscopy- Needle shaped Substance Concentration crystals observed? Aqueous Based Carriers Purified Water 100% Yes, >5 μm, @ 5 days, RT & 60 C. Polysorbate 80 0.5% in water Yes, <5 μm @ 22 days, RT & 60 C. PEG 400 10% in water Yes, >5 μm @ 22 days, RT & 60 C. Benzalkonium 2% in water No, <5 μm @ chloride (50%) 7 days & 21 days, RT Magnesium nitrate 5% in water Yes, >5 μm @ 3 days, RT Mannitol 5% in water Yes, >5 μm, @ 7 days, RT Sorbitol 5% in water Yes, >5 μm, @ 7 days, RT Povidone 1% in water Yes, <5 μm @ 7 days & 21 days, RT Lecithin 1% in water Yes, >10 μm, @ 24 hrs, RT Sodium lauryl 2% in water Yes, >5 μm, @ sulfate 7 days, RT Ammonium lauryl 2% in water Yes, >5 μm @ sulfate 3 days, RT Aluminum sulfate 0.1-0.2% in water Yes, >5 μm, @ 7 days, RT Sodium phosphate 0.75% in water Yes, >5 μm, @ monobasic 7 days, RT Zinc acetate 1.2% in water Yes, >5 μm, @ 7 days, RT Proline 3% in water Yes, >5 μm, @ 7 days, RT Hydroxyethyl 1% in water Yes, >5 μm, @ cellulose 7 days, RT CARBOPOL 0.5% in water No, <5 μm, @ 8 ULTREZ 10 (with days & 21 days, RT Ammonium hydroxide as neutralizer) Hydroxypropyl 1% in water Yes, >5 μm @ methylcellulose 3 days, RT Saline 0.9% NaCl in water Yes, >10 μm, @ 7 days , RT & 60 C. Polysorbate 80 0.5% in Saline Yes, >5 μm @ 7 days, RT & 60 C. Poloxamer 407 2% in water No, <5 μm @ 5 & 7 days, RT Poloxamer 188 2% in water Yes, >5 μm @ 7 days, RT Polyoxyl 40 1% in water Yes, <5 μm @ 6 Hydrogenated days, RT Castor Oil (KOLLIPHOR RH40) Vitamin E TPGS 0.5% in water Yes, <5 μm @ 6 days, RT Hydrophobic Carriers Mineral Oil USP 100% No, <5 μm @ 3 (heavy) days, RT & 40 C. Light Mineral 100% No, <5 μm @ 3 Oil NF days, RT & 40 C. FOMBLIN HC04 100% No, <5 μm @ 4, 7 & 13 days, RT ST-Cyclomethicone 100% No, <5 μm @ 24 5 NF hrs & 13 days, RT Dimethicone, 100% No, <5 μm @ 24 1000 cSt hrs & 6 days, RT Castor Oil 100% No, <5 μm @ 24 hrs & 9 days, RT

The paclitaxel nanoparticles crystals did not grow in any of the hydrophobic carriers. Also, the nanoparticles did not grow in aqueous solutions of benzalkonium chloride, CARBOPOL ULTREZ 10, or poloxamer 407.

Example 3 Particle Size, SSA, and Bulk Density Analysis of Paclitaxel Nanoparticles

The particle size of the paclitaxel nanoparticles lots used in the formulas listed in Table 3 and Tables 16-19 were analyzed by the following particle size method using an ACCUSIZER 780:

Instrument parameters: Max. Concentration: 9000 particles/mL, No. containers: 1, Sensor Range: Summation, Lower Detection Limit: 0.5 μm, Flow Rate: 30 mL/min, No. Analysis pulls: 4, Time between pulls: 1 sec, Pull volume: 10 mL, Tare Volume: 1 mL, Prime volume: 1 mL, Include First Pull: Not Selected.

Sample preparation: Placed a scoop of paclitaxel nanoparticle API into a clean 20 mL vial and added approximately 3 mL of a filtered (0.22 μm) 0.1% w/w solution of SDS to wet the API, then filled the remainder of the vial with the SDS solution. Vortexed for 5-10 minutes and sonicated in a water batch for 1 minute.

Method: Filled a plastic bottle with filtered (0.22 μm) 0.1% w/w SDS solution and analyzed the Background. Pipetted a small amount of the paclitaxel nanoparticles sample suspension, <100 μL, into the bottle of 0.1% w/w SDS solution while stirring; placed the ACCUSIZER inlet tube into the bottle and ran sample through instrument. As necessary, added more SDS solution or paclitaxel sample suspension to reach a desired run concentration of 6000-8000 particle count.

Particles size results (based on number-weighted differential distribution): Paclitaxel nanoparticles lot used in formulas listed in Table 3: Mean: 0.861 μm, Mode: 0.572 μm, Median: 0.710 μm. Paclitaxel nanoparticles lot used in formulas listed in Tables 16-19: Mean: 0.83 μm.

The specific surface area (SSA) of the paclitaxel nanoparticles lots used in the formulas listed in Table 3 and Tables 16-19 were analyzed by the Brunauer-Emmett-Teller (“BET”) isotherm method described above. The paclitaxel nanoparticles lot used in the formulas listed in Table 3 had an SSA of 41.24 m²/g. The paclitaxel nanoparticles lot used in the formulas listed in Tables 16-19 had an SSA of 26.72 m²/g.

The bulk density (not-tapped) of the paclitaxel nanoparticles lot used in the formulas listed in Table 3 was 0.05 g/cm³. The bulk density (not-tapped) of the paclitaxel nanoparticles lot used in the formulas listed in Tables 16-19 was 0.09 g/cm³.

Example 4 Anhydrous Hydrophobic Compositions of Paclitaxel Nanoparticles with Hydrophobic Carriers

Anhydrous hydrophobic compositions of paclitaxel nanoparticles with hydrophobic carriers are listed in Table 3.

TABLE 3 Formula Number Component (% w/w) F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 A B C Paclitaxel 1.0 1.0 1.0 1.0 0.5 2.0 1.0 1.0 1.0 1.0 0.5 0.5 0.5 Nanoparticles FOMBLIN HC04 — — — 15.0  — — — — — — — — — Mineral Oil USP 10.0  — 5.0 — 5.0 5.0 — — — — — — — ST-Cyclomethicone — 5.0 13.0  — 13.0  13.0  13.0  13.0  18.0  15.0  qs ad qs ad qs ad 5 NF(Dow Corning) 100 100 100 Oleyl Alcohol — 5.0 — — — — — 1.0 — — — — 5.0 Isopropyl Myristate — 5.0 — — — — 5.0 1.0 — 3.0 — 35   5.0 NF Dimethicone — — — — — — — — — — 5.0 5.0 5.0 Fumed Silica — — — — — — — — — — 5.5 5.5 2.8 Cetostearyl Alcohol — — — — — — — — 0.5 — — — — NF Paraffin Wax NF 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 — — — White Petrolatum qs ad qs ad qs ad qs ad qs ad qs ad qs ad qs ad qs ad qs ad — — — USP (Spectrum) 100 100 100 100 100 100 100 100 100 100

Procedure for F4-F13: Prepared a slurry of the paclitaxel nanoparticles with a portion of the cyclomethicone (or mineral oil (F4) or FOMBLIN (F7)). Heated the petrolatum to 52±3° C. and added the remaining ingredients and mixed until melted and homogeneous. Added the paclitaxel slurry and mixed until homogenous. Mixed and allowed the batch to cool to 35° C. or below. An ointment was formed.

Example 5 Physical and Chemical Stability of Anhydrous Compositions of Paclitaxel Nanoparticles with Hydrophobic Carriers

The anhydrous hydrophobic composition samples were stored at 25° C. and 30° C. in 20 mL glass scintillation vials. The assay of paclitaxel was conducted using HPLC. The results of the assay and appearance stability studies are shown in Table 4 and Table 5 below. The viscosity was measured at room temperature with a Brookfield RV viscometer using a small sample adapter with a SC4-14 spindle and a 6R chamber at 5 rpm with an equilibration time of 2 minutes. The viscosity results are shown in Table 6 below.

TABLE 4 Stability at 25° C. Assay (% of target) Appearance Formula T = 0 1 month 2 month 3 month T = 0 1 month 2 month 3 month F4 95.3 99.6 100.3 99.5 Off-white Off-white to Off-white to Off-white to ointment yellow ointment yellow ointment yellow ointment F5 98.2 101.7 101.0 100.9 Off-white Off-white to Off-white to Off-white to ointment yellow ointment yellow ointment yellow ointment F6 97.2 100.5 97.9 98.4 Off-white Off-white to Off-white to Off-white to ointment yellow ointment yellow ointment yellow ointment F6** 98.0 98.5 100.2 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F8 107.6 100.5 101.1 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F9 95.6 98.3 101.2 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F10 98.6 103.8 101.2 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F11 99.8 99.8 100.9 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F12 98.7 98.3 99.1 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F13 96.5 93.9 96.0 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment **repeat batch

TABLE 5 Stability at 30° C. Assay (% of target) Appearance Formula T = 0 1 month 2 month 3 month T = 0 1 month 2 month 3 month F4 95.3 99.5 100.1 99.7 Off-white Off-white to Off-white to Off-white to ointment yellow ointment yellow ointment yellow ointment F5 98.2 103.2 101.3 99.2 Off-white Off-white to Off-white to Off-white to ointment yellow ointment yellow ointment yellow ointment F6 97.2 102.1 98.0 95.0 Off-white Off-white to Off-white to Off-white to ointment yellow ointment yellow ointment yellow ointment F6** 98.0 98.7 102.0 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F8 107.6 99.9 103.0 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F9 95.6 101.4 101.9 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F10 98.6 100.9 102.9 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F11 99.8 99.8 99.1 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F12 98.7 99.8 99.5 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment F13 96.5 95.6 96.5 NP Off-white to Off-white to Off-white to NP yellow ointment yellow ointment yellow ointment **repeat batch

TABLE 6 Viscosity Stability Viscosity (cps) F4 F5 F6 F7 T = 0 87,500 44,300 49,500 81,800 1 month @ 25° C. 90,300 68,800 57,000 NP 3 month @ 25° C. 101,000 47,800 38,000 NP 1 month @ 30° C. 123,300 49,300 50,800 NP 2 month @ 30° C. 112,300 53,500 38,000 NP 3 month @ 30° C. 121,300 60,500 54,000 NP

Example 6 Particle Size Analysis of Paclitaxel Nanoparticles in Anhydrous Compositions with Hydrophobic Carriers

Particle Size Method Using an ACCUSIZER Model 770/770A.

Instrument parameters: Sensor: LE 0.5 μm-400 μm, Sensor Range: Summation, Lower Detection Limit: 0.5 μm, Collection time: 60 sec, Number Channels: 128, Vessel Fluid Vol: 100 mL, Flow Rate: 60 mL/min, Max Coincidence: 8000 particles/mL, Sample Vessel: Accusizer Vessel, Sample Calculation: None, Voltage Detector: greater than 10 V, Particle Concentration Calculation: No, Concentration Range: 5000 to 8000 particles/mL, Automatic Data Saving: Selected, Subtract Background: Yes, Number of Autocycles: 1.

Sample Preparation: Added an aliquot of the sample formulation into a scintillation vial. Using a spatula, smeared the sample along the inner walls of the vial. Added about 20 mL of 2% Lecithin in ISOPAR-GTM (C₁₀-11 isoparaffin) solution to the vial. Sonicated the vial for 1 minute. Insured that the sample had adequately dispersed in the solution.

Method: Filled the sample vessel with a filtered (0.22 μm) 2% Lecithin in ISOPAR-G solution and analyzed the background. Using a pipette, transferred a portion of the prepared sample to the vessel while stirring. Diluted or added sample to the vessel as necessary to provide a coincidence level between 5000 to 8000 particles/mL. Initiated the analysis through the instrument and verified that the coincidence level was 5000 to 8000 particles/mL for the analysis.

The results of the particle size analysis are shown in Table 7 and Table 8 below.

TABLE 7 Particle size stability at 25° C. Mean particle size, μm (number) Formula Initial 1 month 3 month 6 month 12 month F4 0.77 0.71 NP NP NP F5 0.72 0.71 NP NP NP F6 0.72 0.71 NP 0.71 0.72 F6** 0.70 NP 0.70 NP NP F8 0.71 NP 0.71 NP NP F9 0.70 NP 0.70 NP NP F10 0.69 NP 0.69 NP NP F11 0.69 NP 0.69 NP NP F12 0.70 NP 0.70 NP NP F13 0.69 NP 0.70 NP NP A 0.72 NP NP NP NP B 0.77 NP NP NP NP C 0.84 NP NP NP NP **repeat batch

TABLE 8 Particle size stability at 30° C. Mean particle size, μm (number) Formula Initial 1 month 3 month 6 month 12 month F4 0.77 0.73 NP NP NP F5 0.72 0.70 NP NP NP F6 0.72 0.70 NP 0.70 0.73 F6** 0.70 NP 0.72 NP NP F8 0.71 NP 0.71 NP NP F9 0.70 NP 0.71 NP NP F10 0.69 NP 0.69 NP NP F11 0.69 NP 0.70 NP NP F12 0.70 NP 0.71 NP NP F13 0.69 NP 0.71 NP NP **repeat batch

As can be seen by the data, the particle size of paclitaxel nanoparticles in samples F4 through F6 did not grow larger than 20% of the initial mean particle size when stored at room temperature (25° C.) and at 30° C. for 1 month. The particle size of paclitaxel nanoparticles in sample F6 did not grow larger than 20% of the initial mean particle size when stored at room temperature (25° C.) and at 30° C. for 6 months and for 12 months. The particle size of paclitaxel nanoparticles in samples F6**(repeat batch with the same formula as F6) and F8 through F13 did not grow larger than 20% of the initial mean particle size when stored at room temperature (25° C.) and at 30° C. for 3 months.

Example 7 Aqueous Based Compositions of Paclitaxel Nanoparticles

Aqueous based compositions of paclitaxel nanoparticles are shown in Table 9.

TABLE 9 Formula Number Component (% w/w) F1 F2 F3 D E F G H Paclitaxel 1.0 1.0 1.0 0.5 0.5 0.5 0.5 0.5 Nanoparticles DGME (TRANSCUTOL P) 5.0 5.0 — 5.0 5.0 5.0 5.0 5.0 PEG 400 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 Glycerin 10.0 10.0 10.0  5.0 5.0 5.0 5.0 5.0 Polysorbate 80 1.0 1.0 1.0 0.1 0.1 0.1 0.1 0.1 Poloxamer 407 2.0 2.0 2.0 — — — — — Povidone K90 0.15 0.15  0.15 0.1 0.1 0.1 0.1 0.1 Benzyl Alcohol 0.5 0.5 0.5 — — — — — Methylparaben 0.15 0.15  0.15  0.15  0.15  0.15  0.15  0.15 Propylparaben 0.02 0.02  0.02  0.02  0.02  0.02  0.02  0.02 Benzalkonium — 1.0 1.0 — — 0.1 0.1 — Chloride (50%) CARBOPOL 974 P — — —  0.75 — — — — CARBOPOL ULTREZ 10 0.5 — — — 0.5 — — — Trolamine Solution qs pH — — qs pH qs pH — — — (10%) 5.5 5.5 5.5 Hydroxypropyl — 1.0 1.0 — — 2.0 — — Methylcellulose (K200M Pharm) Purified Water qs ad qs ad qs ad qs ad qs ad qs ad qs ad qs ad 100 100 100 100 100 100 100 100

Samples were observed for crystal growth of the paclitaxel nanoparticles. The results are shown in Table 10 below.

TABLE 10 Formula Visual observation by light microscopy - Number Needle shaped crystals observed? D No, <5 μm @ 24 hrs & 6 days, RT E No, <5 μm @ 24 hrs & 6 days, RT F No, <5 μm @ 24 hrs & 6 days, RT G No, <5 μm @ 24 hrs & 6 days, RT H Yes, >5 μm @ 24 hrs & 6 days, RT

As can be seen by the data, the presence of benzalkonium chloride, CARBOPOL 974P, or CARBOPOL ULTREZ 10 inhibited the growth of crystals in the aqueous based compositions.

Example 8 Particle Size Analysis of Paclitaxel Nanoparticles in Aqueous Based Compositions

Particle Size Method Using an ACCUSIZER Model 770/770A.

Instrument parameters: Sensor: LE 0.5 μm-400 μm, Sensor Range: Summation, Lower Detection Limit: 0.5 μm, Collection time: 60 sec, Number Channels: 128, Vessel Fluid Vol: 100 mL, Flow Rate: 60 mL/min, Max Coincidence: 8000 particles/mL, Sample Vessel: Accusizer Vessel, Sample Calculation: None, Voltage Detector: greater than 10 V, Particle Concentration Calculation: No, Concentration Range: 5000 to 8000 particles/mL, Automatic Data Saving: Selected, Subtract Background: Yes, Number of Autocycles: 1.

Sample Preparation: Added an aliquot of the sample formulation into a scintillation vial. Using a spatula, smeared the sample along the inner walls of the vial. Added about 20 mL of 0.2 μm filtered distilled water to the vial. Sonicated the vial for 1 minute. Insured that the sample had adequately dispersed in the solution.

Method: Filled the sample vessel with 0.2 μm filtered distilled water and analyzed the background. Using a pipette, transferred a portion of the prepared sample to the vessel while stirring. Diluted or added sample to the vessel as necessary to provide a coincidence level between 5000 to 8000 particles/mL. Initiated the analysis through the instrument and verified that the coincidence level was 5000 to 8000 particles/mL for the analysis.

The results of the particle size analysis are shown in Table 11 below.

TABLE 11 Particle size of aqueous based compositions Mean particle size, μm (number) Formula Initial 6 month at RT F1 1.06 0.82 F2 0.74 0.77 F3 0.70 0.77 D 0.80 NP E 0.79 NP F 0.85 NP

As can be seen by the data of formulas F1, F2, and F3 in Table 11, the presence of benzalkonium chloride, CARBOPOL 974P, or CARBOPOL ULTREZ 10 inhibited the growth of crystals in the aqueous based compositions such that the mean particle size of the drug nanoparticles did not grow larger than 20% of the initial mean particle size when the composition was stored at room temperature for 6 months.

Example 9 In Vitro Skin Penetration Diffusion Study

A study to determine the rate and extent of in vitro skin permeation of the formulas F1 through F13 into and through intact human cadaver skin using a Franz diffusion cell system was conducted. Concentrations of paclitaxel were measured in the receptor chamber of the diffusion cell at varying time points. Upon conclusion of the diffusion study, the skin was tape stripped and split into epidermal and dermal layers. The paclitaxel in the epidermal and dermal tissue was extracted using an extraction solvent and also analyzed.

Analytical Method: A Mass spectrometry (MS) method was developed for analyzing the paclitaxel. The MS conditions were as follows in Table 12 below.

TABLE 12 Instrument: Agilent 1956B MS (TM-EQ-011) Column: XBridge C18 4.6 × 100 mm, 5 μm Mobile Phase: A: Acetonitrile B: 0.1% Formic acid in water Gradient: Time (minutes) % B 0 50%  2 5% 5 5% Flow Rate: 1 mL/min Column Temperature: 30° C. MS Detection: SIM 854.4 + Frag 180, Gain 20 Injection Volume: 20 μL Retention time: ~2.86 min Franz Diffusion Cell (FDC) Study—Methodology

Skin Preparation: Intact human cadaver skin was purchased from New York Firefighters Tissue Bank (NFFTB). The skin was collected from the upper back and dermatomed by the tissue bank to a thickness of −500 μm. Upon receipt of the skin from the tissue bank, the skin was stored frozen at −20° C. until the morning of the experiment. Prior to use, the skin was removed from the freezer and allowed to fully thaw at room temperature. The skin was then briefly soaked in a PBS bath to remove any residual cryoprotectants and preservatives. Only areas of the skin that were visually intact were used during the experiment. For each study, two separate donors were used, each donor having a corresponding three replicates.

Receptor Fluid Preparation: Based on the results of preliminary solubility data, a receptor fluid of 96 wt % phosphate buffered saline (“PBS”) at pH 7.4 and 4 wt % hydroxyl propyl beta cyclodextrin (HPBCD) was chosen. The solubility of the active in the receptor fluid (˜0.4 μg/mL) was shown to be adequate to maintain sink conditions during the studies. The receptor fluid was degassed by filtering the receptor fluid through a ZapCap CR 0.2 μm membrane while pulling vacuum. The filtered receptor fluid was stirred for an additional 20 minutes while maintaining vacuum to ensure complete degassing.

Diffusion Cell Assembly: The cadaver skin was removed from the freezer and allowed to defrost in a bio-safety hood for 30 minutes. The skin was thoroughly defrosted prior to opening the package. The cadaver skin was removed from the package and placed on the bio-safety hood countertop with the stratum corneum side up. The skin was patted dry with a Kim Wipe, then sprayed with fresh PBS and patted dry again. This process was repeated 3 more times to remove any residues present on the skin. The receptor wells were then filled with the degassed receptor fluid. A Teflon coated stir bar was added to each receptor well. The defrosted cadaver skin was examined and only areas with even thickness and no visible damage to the surface were used. The skin was cut into ˜2 cm×2 cm squares. The skin piece was centered on the donor wells, stratum corneum (SC) side up. The skin was centered and the edges flattened out. The donor and receptor wells were then aligned and clamped together with a clamp. Additional receptor fluid was added where necessary. Any air bubbles present were removed by tilting the cell, allowing air to escape along the sample port. Diffusion cells were then placed in to the stirring dry block heaters and allowed to rehydrate for 20 minutes from the receptor fluid. The block heaters were maintained at 32° C. throughout the experiment with continuous stirring. The skin was allowed to hydrate for 20 minutes and the barrier integrity of each skin section was tested. Once the membrane integrity check study was complete, the entire receptor chamber volume was replaced with the receptor fluid.

Formulation Application Procedure: The formulations were applied to the stratum corneum of the skin. A one-time dosing regimen was used for this study. The test articles were applied as 10 μl doses to the skin using a positive displacement Nichiryo pipetter. The formulations were then spread across the surface of the skin using a glass rod. Cells were left uncapped during the experiment. The theoretical dose of paclitaxel per cell is shown in Table 13 below.

TABLE 13 % w/w Nominal Theoretical Formula Paclitaxel formulation Paclitaxel Number in formula dose per cell dose per cell F1 1.0 wt % 10 μl 182 μg/cm² F2 1.0 wt % 10 μl 182 μg/cm² F3 1.0 wt % 10 μl 182 μg/cm² F4 1.0 wt % 10 μl 182 μg/cm² F5 1.0 wt % 10 μl 182 μg/cm² F6 1.0 wt % 10 μl 182 μg/cm² F7 1.0 wt % 10 μl 182 μg/cm² F6* 1.0 wt % 10 μl 182 μg/cm² F8 0.5 wt % 10 μl  91 μg/cm² F9 2.0 wt % 10 μl 364 μg/cm² F10 1.0 wt % 10 μl 182 μg/cm² F11 1.0 wt % 10 μl 182 μg/cm² F12 1.0 wt % 10 μl 182 μg/cm² F13 1.0 wt % 10 μl 182 μg/cm² *repeat analysis

Sampling of Receptor Fluid: At 3, 6, 12 and 24 hours, 300 μL, sample aliquots were drawn from the receptor wells using a graduated Hamilton type injector syringe. Fresh receptor medium was added to replace the 300 μL, sample aliquot.

Tape Stripping and Heat Splitting: At 24 hours, the skin was wiped clean using PBS/ethanol soaked KimWipes. After the residual formulation was wiped off and the skin dried with KimWipes, the stratum corneum was tape stripped three times—each tape stripping consisting of applying cellophane tape to the skin with uniform pressure and peeling the tape off. The tape strips were collected and frozen for future analysis. The first three tape strips remove the uppermost layer of the stratum corneum and act as an extra skin cleaning step. The active is typically not considered fully absorbed in this area. These tape strips are usually only analyzed for a mass balance assay. After the skin was tape stripped, the epidermis of each piece was then separated from the underlying dermal tissue using tweezers or a spatula. The epidermis and dermal tissue were collected and placed in 4 mL borosilicate glass vials. After all the skin pieces were separated, an aliquot of the extraction solvent was added to the glass vial. This process consisted of adding 2 mL of DMSO to the vial and incubating for 24 hours at 32° C. After the extraction time was over, 300 μL sample aliquots of the extraction fluid were collected and filtered.

Analysis of Samples: Sample aliquots were analyzed for paclitaxel using the analytical method as described above.

Results:

The results in Table 14 below show the delivered dose of paclitaxel (μg/cm²) in the receptor fluid at various time points (transdermal flux) and the concentration of paclitaxel (μg/cm²) delivered into the epidermis and dermis (penetration) after 24 hours elapsed time for formulations F1 through F13. FIG. 1 graphically shows the concentration of paclitaxel (μg/cm²) delivered into the epidermis for formulas F1 through F7. FIG. 2 graphically shows the concentration of paclitaxel (μg/cm²) delivered into the epidermis for formulas F6*(repeat analysis) and F8 through F13. FIG. 3 graphically shows the concentration of paclitaxel (μg/cm2) delivered into the dermis for formulas F1 through F7. FIG. 4 graphically shows the concentration of paclitaxel (μg/cm2) delivered into the dermis for formulas F6*(repeat analysis) and F8 through F13.

Note: Formulas F1 through F6 were tested in one in vitro study, and formulas F6* and F8 through F13 were tested in a second separate in vitro study, with different cadaver skin lots. Analysis of formula F6 was repeated in the second study (and notated as F6*) so that it could be evaluated and compared with the other formulas in the second study.

TABLE 14 Paclitaxel Delivered Dose (μg/cm²) Receptor Fluid Receptor Fluid Receptor Fluid Receptor Fluid Formula 3 hrs 6 hrs 12 hrs 24 hrs Epidermis Dermis F1 0.000 0.000 0.000 0.000 0.202 0.030 F2 0.000 0.000 0.000 0.000 0.161 0.042 F3 0.000 0.000 0.000 0.000 0.056 0.138 F4 0.000 0.000 0.000 0.000 0.690 0.639 F5 0.000 0.000 0.000 0.004 0.780 1.337 F6 0.000 0.000 0.000 0.000 1.927 2.088 F7 0.000 0.000 0.000 0.000 0.633 0.882 F6* 0.000 0.000 0.000 0.000 4.910 1.508 F8 0.000 0.000 0.000 0.000 3.155 1.296 F9 0.000 0.000 0.000 0.000 7.010 5.679 F10 0.000 0.000 0.000 0.000 5.470 0.494 F11 0.000 0.000 0.000 0.000 3.262 1.098 F12 0.000 0.000 0.000 0.000 5.269 1.571 F13 0.000 0.000 0.000 0.000 4.903 0.548 *repeat analysis

As can be seen by the results in Table 14, the transdermal flux of the paclitaxel through the skin (epidermis and dermis) was none or only a negligible amount, i.e., less than 0.01 μg/cm². As can be seen by the results in Table 14 and FIGS. 1, 2, 3 & 4, the penetration of paclitaxel into the skin (epidermis and dermis) was far greater with the anhydrous hydrophobic formulations (F4 through F13) than with the aqueous formulations (F1 through F3), even though the aqueous formulations contained the skin penetration enhancer DGME (TRANSCUTOL P). The results also show that the anhydrous hydrophobic formulations with cyclomethicone exhibited greater skin penetration (epidermis and dermis) over the anhydrous hydrophobic formulations without cyclomethicone. Additionally, the results show that the addition of other skin penetration enhancers to the anhydrous hydrophobic formulations containing cyclomethicone had little or no effect on the skin penetration (epidermis and dermis) of these compositions.

Example 10—Formulations for Cutaneous Metastasis Studies

The following ointment formulations shown in Table 15 were prepared for use in cutaneous metastasis studies.

TABLE 15 Formula No. F14 F15 F16 F17 Component (% w/w) (0.15%) (0.3%) (1%) (2%) Paclitaxel Nanoparticles 0.15 0.3 1.0 2.0 Mineral Oil USP 5.0 5.0 5.0 5.0 ST-Cyclomethicone 5 NF 13.0 13.0 13.0 13.0 (Dow Corning) Paraffin Wax NF 5.0 5.0 5.0 5.0 White Petrolatum USP qs ad 100 qs ad 100 qs ad 100 qs ad 100 (Spectrum)

The formulas listed in Table 15 containing paclitaxel nanoparticles were manufactured each in a 6 kg batch size. The formulas were then packaged in 15 gm laminate tubes.

The manufacturing processes for lots F14, F15, and F16 were as follows: The petrolatum, mineral oil, paraffin wax, and a portion of the cyclomethicone were added to a vessel and heated to 52±3° C. while mixing with a propeller mixer until melted and homogeneous. The paclitaxel nanoparticles were added to a vessel containing another portion of cyclomethicone and first mixed with a spatula to wet the nanoparticles, then mixed with an IKA Ultra Turrax Homogenizer with a S25-25G dispersing tool until a homogeneous slurry is obtained while keeping the container in an ice/water bath. The slurry was then added to the petrolatum/paraffin wax container while mixing with the propeller mixer followed by rinsing with the remaining portion of cyclomethicone and mixed until the batch was visually homogeneous while at 52±3° C. The batch was then homogenized using a Silverson homogenizer. Afterward, the batch was mixed with a propeller mixer until a homogeneous ointment was formed and the batch cooled to 35° C. or below.

The manufacturing process for lot F17 was as follows: The petrolatum and paraffin wax were added to a vessel and heated to 52±3° C. while mixing with a propeller mixer until melted and homogeneous. The paclitaxel nanoparticles were added to a vessel containing the cyclomethicone and a portion of mineral oil, and first mixed with a spatula to wet the nanoparticles, then mixed with an IKA Ultra Turrax Homogenizer with a S25-25G dispersing tool until a homogeneous slurry is obtained while keeping the container in an ice/water batch. The slurry was then added to the petrolatum/paraffin wax container while mixing with the propeller mixer followed by rinsing with the remaining portion of mineral oil and mixed until the batch was visually homogeneous while at 52±3° C. The batch was then homogenized using a Silverson homogenizer. Afterward, the batch was mixed with a propeller mixer until a homogeneous ointment was formed and the batch cooled to 35° C. or below.

The chemical and physical analytical results for each formula in Table 15 are shown in Tables 16-19 for T=0, 1 month, and 3 months at 25° C.

TABLE 16 Formula No. F14 (0.15%) Test T = 0 1 month 3 month Appearance (note 1) conforms conforms conforms Assay, % target 103.4 103.2 101.1 Viscosity (note 2) 131000 cps 147000 cps 159500 cps Mean Particle Size (number) 0.71 μm 0.70 μm 0.70 μm (note 1): Off-white to yellow ointment (note 2): Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds.

TABLE 17 Formula No. F15 (0.3%) Test T = 0 1 month 3 month Appearance (note 1) conforms conforms conforms Assay, % target 101.2 101.9 102.5 Viscosity (note 2) 195500 cps 154000 cps 153500 cps Mean Particle Size (number) 0.72 μm 0.71 μm 0.70 μm (note 1): Off-white to yellow ointment (note 2): Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds.

TABLE 18 Formula No. F16 (1%) Test T = 0 1 month 3 month Appearance (note 1) conforms conforms conforms Assay, % target 102.1 102.2 102.7 Viscosity (note 2) 205000 cps 218000 cps 180000 cps Mean Particle Size (number) 0.70 μm 0.70 μm 0.70 μm (note 1): Off-white to yellow ointment (note 2): Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds.

TABLE 19 Formula No. F17 (2%) Test T = 0 1 month 3 month Appearance (note 1) conforms conforms conforms Assay, % target 101.7 101.1 105.0 Viscosity (note 2) 158000 cps 177000 cps 162000 cps Mean Particle Size (number) 0.70 μm 0.69 μm 0.69 μm (note 1): Off-white to yellow ointment (note 2): Brookfield RV viscometer on a helipath stand with the helipath on, with a T-E spindle at 10 RPM at room temperature for 45 seconds.

Example 11—Individual Patient Expanded Access Trial for Topical Treatment of Cutaneous Metastatic Breast Cancer

The formulations in Table 15 are to be used in an individual human patient expanded access trial for topical treatment of cutaneous metastatic breast cancer. In this expanded access trial, a subject with cutaneous metastasis from breast cancer will receive topical application of 0.3% paclitaxel nanoparticles ointment (formula F15 from Table 15) to the affected area. Prior to study entry, historical information will be collected from the subject including surgical history, radiation history, chemotherapy, and time-to-ulceration for other cutaneous metastases. Photographs (with a ruler) and measurements of metastasis (treatment area) will be taken in the clinic prior to initiation of treatment. No biopsies or blood work will be done. Prior to application, the treatment area will be gently cleansed with water (and mild soap if required) and dried. The subject will apply the ointment with a gloved hand over metastases which have skin covering (epithelial/dermal covering). The ointment will not be applied on ulcerated areas. A layer of ointment the “thickness of a dime” will be applied on metastasis as directed by clinical medical staff at the first treatment. The ointment application site will be covered with an occlusive dressing (TEGADERM or SOLOSITE). The subject will re-treat the metastasis once daily at approximately the same time for two weeks using the same technique as the initial application. The subject will then return to the clinic for review of response and any adverse events will be recorded in the clinic record. A photograph will be taken of the treated site (with a ruler) and the lesion will be measured. The subject can be treated for another two weeks with physician approval, and the subject will return to the clinic for a final visit where photographs of the treatment site (with a ruler) will be taken and the lesion will be measured. Adverse events will be recorded in clinic records. If requested by the subject and the physician, a higher or lower dose following the above plan may be authorized after a review of data and discussion with the physician. No wash out period will be required. If requested by the subject and the physician, further treatment with the same dose (0.3% paclitaxel nanoparticles ointment), a dose escalation (1.0% and/or 2.0% paclitaxel nanoparticles ointment), or a dose deescalation (0.15% paclitaxel nanoparticles ointment) may be authorized after a review of data, and discussion with the physician. If erythema, cracking or ulceration develop, the subject will wash the treatment site with water (and mild soap if required) and return to the clinic for evaluation. A photograph (with a ruler) will be taken of the treatment site, the lesion will be measured, and no further ointment will be applied unless approved by the physician. The endpoint of the trial will show a reduction of the cutaneous metastasis demonstrating a therapeutic improvement of the cutaneous metastatic condition.

Example 12—Phase ½ Dose-Rising, Safety, Tolerability and Efficacy Study for Cutaneous Metastases

Three of the formulations in Table 15 above were used in a FDA approved Phase ½ dose-rising, safety, tolerability and efficacy study for cutaneous metastases in humans. The study is currently on-going. This was a Phase ½, open-label, dose-rising study evaluating the safety tolerability, and preliminary efficacy of three of the formulations from Table 15: F14 (0.15%), F16 (1.0%), and F17 (2.0%) applied topically twice daily for 28 days to non-melanoma cutaneous metastases.

A treatment area of 50 cm² on the trunk or extremities containing at least one eligible lesion was determined at baseline by the RECIST (version 1.1) definition of measurable tumors (greater than or equal to 10 mm in its longest diameter). All lesions within the treatment area were measured by caliper to confirm eligibility. Using a gloved hand, subjects applied one fingertip unit (FTU) of the formulation to the 50 cm² treatment area twice daily at approximately the same time each day for 28 days. A FTU is defined as the amount of ointment formulation expressed from a tube with a 5-mm diameter nozzle, applied from the distal skin-crease to the tip of the index finger of an adult. Subjects attended the clinic on Day 1 for dose application training and observation of the first treatment application. Additional visits were on Days 8, 15, 29, and 43. The final visit was completed 30 days after the last study drug dose to review adverse events. Study participation is separated into a dose-escalation phase and a dose expansion phase.

Dose Escalation Phase: During the dose-escalation phase the study followed a standard 3+3 dose-ascending design, with the first cohort of three subjects commencing treatment with formulation F14 (0.15%). A safety monitoring committee reviewed all available data after the last subject in each cohort of three subjects completed 15 days of treatment to determine whether dose escalation may continue.

Dose Expansion Phase: In the dose-expansion phase, additional subjects were enrolled to reach a maximum of 12 total subjects at the dose level determined in the dose escalation phase. Subjects in the dose expansion phase attended the clinic on the same visit days and received the same evaluations as the dose escalation phase above.

Objectives: The primary objective of the study was to determine the preliminary safety and tolerability of the formulations. The secondary objectives were to determine the preliminary efficacy of the formulations, to study potential reduction in pain in the treatment area, and to describe the pharmacokinetics of the formulations applied to metastatic lesions.

Population: A minimum of two up to a maximum of 24 male and female human subjects, greater than or equal to 18 years of age, with non-melanoma cutaneous metastases.

Primary Endpoint: Safety and tolerability, as demonstrated by adverse events, changes in laboratory assessments, physical examination findings, and vital signs.

Secondary Endpoints: For the purposes of the following secondary endpoint for efficacy, eligible lesions were determined at baseline by the RECIST (Version 1.1) definition of measurable tumors (greater than or equal to 10 mm in its longest diameter (EISENHAUER et al. New response evaluation criteria in solid tumors: revised RECIST guideline (version 1.1). European Journal of Cancer. 2009; 45; 228-247).

Objective Tumor Response, defined as the difference in the sum of eligible tumor diameter(s) within the treatment area between baseline and Day 43 (i.e., 14 days after the last dose in the dose escalation and expansion phases depending on dose regimen). Tumor surface area and response were assessed at all visits. Change in surface area was assessed using a calibrated grid measurement system (ImageJ freeware) provided by the National Institutes of Health (NIH). Lesions were measured and analyzed using ImageJ.

Objective Clinical Response is defined as subjects with Complete Clinical Response (CR)+Partial Response (PR), further defined as the percentage of patients who achieve complete clinical response or partial response 14 days after the last treatment with the formulation, measured as change in the sum of the longest diameter(s) of eligible target lesion(s) within the treatment area 14 days after last treatment. The response to treatment was evaluated as a function of post-treatment total diameter divided by pre-treatment total diameter.

Best Overall Response is defined as the best response recorded from the start of the study treatment until the end of treatment, i.e., Day 43.

Complete Clinical Response (CR) is defined as absence of any detectable residual disease in eligible lesion(s) within the treatment area; Partial Response (PR) is at least a 30% decrease in the sum of the diameters of the eligible lesions(s) within the treatment area compared to bassline; and Progressive Disease (PD) is at least a 20% increase in the sum of diameters of eligible lesion(s) within the treatment area, taking as a reference the smallest sum on study. In addition, the sum must also demonstrate an absolute increase of at least 5 mm. Stable Disease (SD) is defined as the sum of eligible lesion diameter(s) between that defined as PR or PD.

The appearance of new non-target lesions during participation in this study does not constitute progressive disease.

Pain at the treatment area will be measures by the Numeric Rating Scale (NRS-11). Change in pain will be analyzed from baseline to Day 43.

Systemic exposure as determined by: T_(max), C_(max), AUC.

Preliminary Results: Preliminary results for the on-going study include photos of skin metastatic lesions on the chest of a woman with Stage 4 breast cancer. FIG. 5 is a photo taken at baseline (Day 1) and shows the index lesion (arrow) covered with congealed exudate from an ulcerated lesion. FIG. 6 is a photo taken at Day 8 after topical treatment of the formulation F14 (0.15%) applied over the same treatment site twice per day. The surface of the lesion contains an area of epidermal loss and presumptive ulceration limited to the dermis. FIG. 7 is a photo at Day 15 after topical treatment of the formulation F14 (0.15%) applied over the same treatment site twice per day. A small amount of old exudate can be seen on the medial portion of the lesion as well as no apparent epidermal ulceration. FIG. 8 is a photo at Day 29 after topical treatment of the formulation F14 (0.15%) applied over the same treatment site twice per day. The lesion appears to be epithelialized with no evidence of ulceration. In contrast, the natural history of an ulcerative cutaneous breast cancer metastasis is rapid expansion and further penetration through the dermis once the epidermal surface is breached by the tumor. Thus, the topical application of the treatment formulations to cutaneous metastatic disease provides a benefit to the patients.

Example 13—Dermal Toxicity Study

A dermal toxicity study was conducted using the formulations shown in Table 20.

TABLE 20 Formula No. F18 (0.0%) F19 F20 F21 Component (% w/w) Placebo (0.3%) (1%) (3%) Paclitaxel Nanoparticles 0.0 0.3 1.0 3.0 Mineral Oil USP 5.0 5.0 5.0 5.0 ST-Cyclomethicone 5 13.0 13.0 13.0 13.0 NF (Dow Corning) Paraffin Wax NF 5.0 5.0 5.0 5.0 White Petrolatum USP qs qs qs qs (Spectrum) ad 100 ad 100 ad 100 ad 100

The GLP-compliant study was conducted in Gottingen minipigs to characterize the toxicity of the formulations applied topically to 10% body surface area daily for 28 days. The 4 formulations shown in Table 20 were applied at the maximal feasible volume of 2 mL/kg, correlating to dose concentrations of 0.0, 0.3, 1.0, and 3%, which translate to dose levels of 0, 4.9, 16.5, and 49.9 mg/kg/day respectively. Reversibility of findings was also evaluated following a 2-week recovery period. Parameters evaluated included clinical observations, mortality and moribundity checks, dermal scoring, body weight, food consumption, eye examinations, test site photographs, electrocardiology, clinical pathology, bioanalysis and toxicokinetic evaluation, organ weights, macroscopic pathology and histopathology. There were no formulation-related effects on survival, clinical signs, dermal irritation, body weights, body weight gains, food consumption, ophthalmic findings, or cardiology parameters. Minimal dermal irritation was observed in all groups during the dosing phase and was considered vehicle or procedurally related as the frequency and severity of the findings were comparable between the placebo controls and active formulation-treated groups. Thus, the presence of the paclitaxel nanoparticles in the formulations had a negligible effect on dermal irritation. 

The invention claimed is:
 1. A method of treating a skin malignancy in a subject in need of treatment, the method comprising topically administering to an affected area of the subject a hydrophobic composition comprising a hydrophobic carrier and a plurality of nanoparticles of non-solubilized taxane, wherein the plurality of nanoparticles of non-solubilized taxane are uncoated (neat) individual particles of non-solubilized taxane, and wherein the non-solubilized taxane is not bound to or conjugated to any substance.
 2. The method of claim 1, wherein the nanoparticles of non-solubilized taxane are in crystalline form.
 3. The method of claim 1, wherein the nanoparticles of non-solubilized taxane are in amorphous form.
 4. The method of claim 1, wherein the nanoparticles of non-solubilized taxane have a mean particle size (number) from 0.1 microns to 1.5 microns.
 5. The method of claim 1, wherein the taxane is paclitaxel.
 6. The method of claim 5, wherein the nanoparticles of non-solubilized taxane have a specific surface area (SSA) of 18 m²/g to 40 m²/g.
 7. The method of claim 6, wherein the nanoparticles of non-solubilized taxane contain not less than 90% by weight of paclitaxel.
 8. The method of claim 1, wherein the composition comprises 0.1% w/w to 5% w/w of the plurality of the nanoparticles of non-solubilized taxane.
 9. The method of claim 1, wherein the nanoparticles of non-solubilized taxane are suspended within the composition.
 10. The method of claim 1, wherein the composition is anhydrous.
 11. The method of claim 1, wherein the composition comprises greater than 50% w/w of the hydrophobic carrier.
 12. The method of claim 1, wherein the hydrophobic carrier is non-volatile and non-polar.
 13. The method of claim 1, wherein the hydrophobic carrier comprises a hydrocarbon.
 14. The method of claim 13, wherein the hydrocarbon is petrolatum, mineral oil, or paraffin wax, or mixtures thereof.
 15. The method of claim 1, wherein the composition comprises one or more volatile silicone fluids.
 16. The method of claim 15, wherein the composition comprises 5% w/w to 24% w/w of the one or more volatile silicone fluids.
 17. The method of claim 15, wherein the one or more volatile silicone fluids comprises cyclomethicone.
 18. The method of claim 1, wherein the composition does not contain a C₁-C₄ aliphatic alcohol, a surfactant, a protein, or a hyaluronic acid-taxane conjugate.
 19. The method of claim 1, wherein the skin malignancy is a skin cancer.
 20. The method of claim 19, wherein the skin cancer is melanoma, basal cell carcinoma, squamous cell carcinoma, or Kaposi's sarcoma.
 21. The method of claim 1, wherein the skin malignancy is a cutaneous metastasis.
 22. The method of claim 21, wherein the cutaneous metastasis is from lung cancer, breast cancer, colon cancer, oral cancer, ovarian cancer, kidney cancer, esophageal cancer, stomach cancer, liver cancer, or Kaposi's sarcoma. 